diff --git a/java-core/google-cloud-core/clirr-ignored-differences.xml b/java-core/google-cloud-core/clirr-ignored-differences.xml
index 0f7f80a7b4..6792bcb968 100644
--- a/java-core/google-cloud-core/clirr-ignored-differences.xml
+++ b/java-core/google-cloud-core/clirr-ignored-differences.xml
@@ -12,4 +12,10 @@
         <className>com/google/cloud/ReadChannel</className>
         <method>long limit()</method>
     </difference>
+    <difference>
+        <!-- Default method added to interface -->
+        <differenceType>7012</differenceType>
+        <className>com/google/cloud/testing/BaseEmulatorHelper$EmulatorRunner</className>
+        <method>int waitForDuration(java.time.Duration)</method>
+    </difference>
 </differences>
diff --git a/java-core/google-cloud-core/src/main/java/com/google/cloud/RetryOption.java b/java-core/google-cloud-core/src/main/java/com/google/cloud/RetryOption.java
index a1069b48a2..f69b0d1c76 100644
--- a/java-core/google-cloud-core/src/main/java/com/google/cloud/RetryOption.java
+++ b/java-core/google-cloud-core/src/main/java/com/google/cloud/RetryOption.java
@@ -16,12 +16,13 @@
 
 package com.google.cloud;
 
+import static com.google.api.gax.util.TimeConversionUtils.toJavaTimeDuration;
 import static com.google.common.base.Preconditions.checkNotNull;
 
 import com.google.api.core.BetaApi;
+import com.google.api.core.ObsoleteApi;
 import com.google.api.gax.retrying.RetrySettings;
 import java.io.Serializable;
-import org.threeten.bp.Duration;
 
 /**
  * This class represents an options wrapper around the {@link RetrySettings} class and is an
@@ -51,13 +52,25 @@ private RetryOption(OptionType type, Object value) {
     this.value = checkNotNull(value);
   }
 
-  /** See {@link RetrySettings#getTotalTimeout()}. */
-  public static RetryOption totalTimeout(Duration totalTimeout) {
+  /** This method is obsolete. Use {@link #totalTimeoutDuration(java.time.Duration)} instead */
+  @ObsoleteApi("Use totalTimeouDuration() instead")
+  public static RetryOption totalTimeout(org.threeten.bp.Duration totalTimeout) {
+    return totalTimeoutDuration(toJavaTimeDuration(totalTimeout));
+  }
+
+  /** See {@link RetrySettings#getTotalTimeoutDuration()}. */
+  public static RetryOption totalTimeoutDuration(java.time.Duration totalTimeout) {
     return new RetryOption(OptionType.TOTAL_TIMEOUT, totalTimeout);
   }
 
-  /** See {@link RetrySettings#getInitialRetryDelay()}. */
-  public static RetryOption initialRetryDelay(Duration initialRetryDelay) {
+  /** This method is obsolete. Use {@link #initialRetryDelayDuration(java.time.Duration)} instead */
+  @ObsoleteApi("Use initialRetryDelayDuration() instead")
+  public static RetryOption initialRetryDelay(org.threeten.bp.Duration initialRetryDelay) {
+    return initialRetryDelayDuration(toJavaTimeDuration(initialRetryDelay));
+  }
+
+  /** See {@link RetrySettings#getInitialRetryDelayDuration()}. */
+  public static RetryOption initialRetryDelayDuration(java.time.Duration initialRetryDelay) {
     return new RetryOption(OptionType.INITIAL_RETRY_DELAY, initialRetryDelay);
   }
 
@@ -66,8 +79,14 @@ public static RetryOption retryDelayMultiplier(double retryDelayMultiplier) {
     return new RetryOption(OptionType.RETRY_DELAY_MULTIPLIER, retryDelayMultiplier);
   }
 
-  /** See {@link RetrySettings#getMaxRetryDelay()}. */
-  public static RetryOption maxRetryDelay(Duration maxRetryDelay) {
+  /** This method is obsolete. Use {@link #maxRetryDelayDuration(java.time.Duration)} instead */
+  @ObsoleteApi("Use maxRetryDelayDuration() instead")
+  public static RetryOption maxRetryDelay(org.threeten.bp.Duration maxRetryDelay) {
+    return maxRetryDelayDuration(toJavaTimeDuration(maxRetryDelay));
+  }
+
+  /** See {@link RetrySettings#getMaxRetryDelayDuration()}. */
+  public static RetryOption maxRetryDelayDuration(java.time.Duration maxRetryDelay) {
     return new RetryOption(OptionType.MAX_RETRY_DELAY, maxRetryDelay);
   }
 
@@ -124,16 +143,16 @@ public static RetrySettings mergeToSettings(RetrySettings settings, RetryOption.
     for (RetryOption option : options) {
       switch (option.type) {
         case TOTAL_TIMEOUT:
-          builder.setTotalTimeout((Duration) option.value);
+          builder.setTotalTimeoutDuration((java.time.Duration) option.value);
           break;
         case INITIAL_RETRY_DELAY:
-          builder.setInitialRetryDelay((Duration) option.value);
+          builder.setInitialRetryDelayDuration((java.time.Duration) option.value);
           break;
         case RETRY_DELAY_MULTIPLIER:
           builder.setRetryDelayMultiplier((Double) option.value);
           break;
         case MAX_RETRY_DELAY:
-          builder.setMaxRetryDelay((Duration) option.value);
+          builder.setMaxRetryDelayDuration((java.time.Duration) option.value);
           break;
         case MAX_ATTEMPTS:
           builder.setMaxAttempts((Integer) option.value);
diff --git a/java-core/google-cloud-core/src/main/java/com/google/cloud/ServiceOptions.java b/java-core/google-cloud-core/src/main/java/com/google/cloud/ServiceOptions.java
index 985fac4804..92aaa9d6a9 100644
--- a/java-core/google-cloud-core/src/main/java/com/google/cloud/ServiceOptions.java
+++ b/java-core/google-cloud-core/src/main/java/com/google/cloud/ServiceOptions.java
@@ -63,6 +63,7 @@
 import java.io.Serializable;
 import java.nio.charset.Charset;
 import java.nio.charset.StandardCharsets;
+import java.time.Duration;
 import java.util.Locale;
 import java.util.Map;
 import java.util.Objects;
@@ -70,7 +71,6 @@
 import java.util.Set;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
-import org.threeten.bp.Duration;
 
 /**
  * Abstract class representing service options.
@@ -787,13 +787,13 @@ public static RetrySettings getNoRetrySettings() {
   private static RetrySettings.Builder getDefaultRetrySettingsBuilder() {
     return RetrySettings.newBuilder()
         .setMaxAttempts(6)
-        .setInitialRetryDelay(Duration.ofMillis(1000L))
-        .setMaxRetryDelay(Duration.ofMillis(32_000L))
+        .setInitialRetryDelayDuration(Duration.ofMillis(1000L))
+        .setMaxRetryDelayDuration(Duration.ofMillis(32_000L))
         .setRetryDelayMultiplier(2.0)
-        .setTotalTimeout(Duration.ofMillis(50_000L))
-        .setInitialRpcTimeout(Duration.ofMillis(50_000L))
+        .setTotalTimeoutDuration(Duration.ofMillis(50_000L))
+        .setInitialRpcTimeoutDuration(Duration.ofMillis(50_000L))
         .setRpcTimeoutMultiplier(1.0)
-        .setMaxRpcTimeout(Duration.ofMillis(50_000L));
+        .setMaxRpcTimeoutDuration(Duration.ofMillis(50_000L));
   }
 
   protected abstract Set<String> getScopes();
diff --git a/java-core/google-cloud-core/src/main/java/com/google/cloud/Timestamp.java b/java-core/google-cloud-core/src/main/java/com/google/cloud/Timestamp.java
index e0308c3836..bcdbe17b72 100644
--- a/java-core/google-cloud-core/src/main/java/com/google/cloud/Timestamp.java
+++ b/java-core/google-cloud-core/src/main/java/com/google/cloud/Timestamp.java
@@ -18,11 +18,16 @@
 
 import static com.google.common.base.Preconditions.checkArgument;
 
+import com.google.api.core.ObsoleteApi;
 import com.google.protobuf.util.Timestamps;
 import java.io.Serializable;
-import java.util.Date;
-import java.util.Objects;
-import java.util.concurrent.TimeUnit;
+//import java.time.Instant;
+//import java.time.LocalDateTime;
+//import java.time.ZoneOffset;
+//import java.time.format.DateTimeFormatter;
+//import java.time.format.DateTimeFormatterBuilder;
+//import java.time.format.DateTimeParseException;
+//import java.time.temporal.TemporalAccessor;
 import org.threeten.bp.Instant;
 import org.threeten.bp.LocalDateTime;
 import org.threeten.bp.ZoneOffset;
@@ -30,6 +35,9 @@
 import org.threeten.bp.format.DateTimeFormatterBuilder;
 import org.threeten.bp.format.DateTimeParseException;
 import org.threeten.bp.temporal.TemporalAccessor;
+import java.util.Date;
+import java.util.Objects;
+import java.util.concurrent.TimeUnit;
 
 /**
  * Represents a timestamp with nanosecond precision. Timestamps cover the range [0001-01-01,
@@ -54,7 +62,7 @@ public final class Timestamp implements Comparable<Timestamp>, Serializable {
       new DateTimeFormatterBuilder()
           .appendOptional(DateTimeFormatter.ISO_LOCAL_DATE_TIME)
           .optionalStart()
-          .appendOffsetId()
+          .appendZoneOrOffsetId()
           .optionalEnd()
           .toFormatter()
           .withZone(ZoneOffset.UTC);
@@ -189,6 +197,17 @@ public com.google.protobuf.Timestamp toProto() {
     return com.google.protobuf.Timestamp.newBuilder().setSeconds(seconds).setNanos(nanos).build();
   }
 
+  /** This method is obsolete. Use {@link #parseTimestampDuration(String)} instead */
+  @ObsoleteApi("Use parseTimestampDuration(String) instead")
+  public static Timestamp parseTimestamp(String timestamp) {
+    try {
+      return parseTimestampDuration(timestamp);
+    } catch (DateTimeParseException ex) {
+      throw new org.threeten.bp.format.DateTimeParseException(
+          ex.getMessage(), ex.getParsedString(), ex.getErrorIndex());
+    }
+  }
+
   /**
    * Creates a Timestamp instance from the given string. Input string should be in the RFC 3339
    * format, like '2020-12-01T10:15:30.000Z' or with the timezone offset, such as
@@ -198,7 +217,7 @@ public com.google.protobuf.Timestamp toProto() {
    * @return created Timestamp
    * @throws DateTimeParseException if unable to parse
    */
-  public static Timestamp parseTimestamp(String timestamp) {
+  public static Timestamp parseTimestampDuration(String timestamp) {
     TemporalAccessor temporalAccessor = timestampParser.parse(timestamp);
     Instant instant = Instant.from(temporalAccessor);
     return ofTimeSecondsAndNanos(instant.getEpochSecond(), instant.getNano());
diff --git a/java-core/google-cloud-core/src/main/java/com/google/cloud/testing/BaseEmulatorHelper.java b/java-core/google-cloud-core/src/main/java/com/google/cloud/testing/BaseEmulatorHelper.java
index 9679c6299c..93f7ea0f59 100644
--- a/java-core/google-cloud-core/src/main/java/com/google/cloud/testing/BaseEmulatorHelper.java
+++ b/java-core/google-cloud-core/src/main/java/com/google/cloud/testing/BaseEmulatorHelper.java
@@ -16,8 +16,12 @@
 
 package com.google.cloud.testing;
 
+import static com.google.api.gax.util.TimeConversionUtils.toJavaTimeDuration;
+import static com.google.api.gax.util.TimeConversionUtils.toThreetenDuration;
+
 import com.google.api.core.CurrentMillisClock;
 import com.google.api.core.InternalApi;
+import com.google.api.core.ObsoleteApi;
 import com.google.cloud.ExceptionHandler;
 import com.google.cloud.RetryHelper;
 import com.google.cloud.ServiceOptions;
@@ -56,7 +60,6 @@
 import java.util.logging.Logger;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipInputStream;
-import org.threeten.bp.Duration;
 
 /** Utility class to start and stop a local service which is used by unit testing. */
 @InternalApi
@@ -112,14 +115,21 @@ protected final void startProcess(String blockUntilOutput)
     }
   }
 
+  /** This method is obsolete. Use {@link #waitForProcessDuration(java.time.Duration)} instead */
+  @ObsoleteApi("Use waitForProcessDuration(java.time.Duration) instead")
+  protected final int waitForProcess(org.threeten.bp.Duration timeout)
+      throws IOException, InterruptedException, TimeoutException {
+    return waitForProcessDuration(toJavaTimeDuration(timeout));
+  }
+
   /**
    * Waits for the local service's subprocess to terminate, and stop any possible thread listening
    * for its output.
    */
-  protected final int waitForProcess(Duration timeout)
+  protected final int waitForProcessDuration(java.time.Duration timeout)
       throws IOException, InterruptedException, TimeoutException {
     if (activeRunner != null) {
-      int exitCode = activeRunner.waitFor(timeout);
+      int exitCode = activeRunner.waitForDuration(timeout);
       activeRunner = null;
       return exitCode;
     }
@@ -130,7 +140,7 @@ protected final int waitForProcess(Duration timeout)
     return 0;
   }
 
-  private static int waitForProcess(final Process process, Duration timeout)
+  private static int waitForProcess(final Process process, java.time.Duration timeout)
       throws InterruptedException, TimeoutException {
     if (process == null) {
       return 0;
@@ -180,10 +190,17 @@ public String getProjectId() {
   /** Starts the local emulator. */
   public abstract void start() throws IOException, InterruptedException;
 
-  /** Stops the local emulator. */
-  public abstract void stop(Duration timeout)
+  /** This method is obsolete. Use {@link #stopDuration(java.time.Duration)} instead */
+  @ObsoleteApi("Use stopDuration() instead")
+  public abstract void stop(org.threeten.bp.Duration timeout)
       throws IOException, InterruptedException, TimeoutException;
 
+  /** Stops the local emulator. */
+  public void stopDuration(java.time.Duration timeout)
+      throws IOException, InterruptedException, TimeoutException {
+    stop(toThreetenDuration(timeout));
+  }
+
   /** Resets the internal state of the emulator. */
   public abstract void reset() throws IOException;
 
@@ -226,8 +243,15 @@ protected interface EmulatorRunner {
     /** Starts the emulator associated to this runner. */
     void start() throws IOException;
 
+    /** This method is obsolete. Use {@link #waitForDuration(java.time.Duration)} instead */
+    @ObsoleteApi("Use waitForDuration() instead")
+    int waitFor(org.threeten.bp.Duration timeout) throws InterruptedException, TimeoutException;
+
     /** Wait for the emulator associated to this runner to terminate, returning the exit status. */
-    int waitFor(Duration timeout) throws InterruptedException, TimeoutException;
+    default int waitForDuration(java.time.Duration timeout)
+        throws InterruptedException, TimeoutException {
+      return waitFor(toThreetenDuration(timeout));
+    }
 
     /** Returns the process associated to the emulator, if any. */
     Process getProcess();
@@ -263,9 +287,17 @@ public void start() throws IOException {
       log.fine("Starting emulator via Google Cloud SDK");
       process = CommandWrapper.create().setCommand(commandText).setRedirectErrorStream().start();
     }
+    /** This method is obsolete. Use {@link #waitForDuration(java.time.Duration)} instead */
+    @ObsoleteApi("Use waitForDuration() instead")
+    @Override
+    public int waitFor(org.threeten.bp.Duration timeout)
+        throws InterruptedException, TimeoutException {
+      return waitForDuration(toJavaTimeDuration(timeout));
+    }
 
     @Override
-    public int waitFor(Duration timeout) throws InterruptedException, TimeoutException {
+    public int waitForDuration(java.time.Duration timeout)
+        throws InterruptedException, TimeoutException {
       return waitForProcess(process, timeout);
     }
 
@@ -374,8 +406,16 @@ public Path call() throws IOException {
               .start();
     }
 
+    /** This method is obsolete. Use {@link #waitForDuration(java.time.Duration)} instead */
+    @ObsoleteApi("Use waitForDuration() instead")
     @Override
-    public int waitFor(Duration timeout) throws InterruptedException, TimeoutException {
+    public int waitFor(org.threeten.bp.Duration timeout)
+        throws InterruptedException, TimeoutException {
+      return waitForDuration(toJavaTimeDuration(timeout));
+    }
+
+    public int waitForDuration(java.time.Duration timeout)
+        throws InterruptedException, TimeoutException {
       return waitForProcess(process, timeout);
     }
 
diff --git a/java-core/google-cloud-core/src/test/java/com/google/cloud/RetryOptionTest.java b/java-core/google-cloud-core/src/test/java/com/google/cloud/RetryOptionTest.java
index a458d31f67..192cc21f5f 100644
--- a/java-core/google-cloud-core/src/test/java/com/google/cloud/RetryOptionTest.java
+++ b/java-core/google-cloud-core/src/test/java/com/google/cloud/RetryOptionTest.java
@@ -20,27 +20,30 @@
 import static org.junit.jupiter.api.Assertions.assertNotEquals;
 
 import com.google.api.gax.retrying.RetrySettings;
+import java.time.Duration;
 import org.junit.jupiter.api.Test;
-import org.threeten.bp.Duration;
 
 class RetryOptionTest {
+  private static final long TOTAL_TIMEOUT_MILLIS = 420l;
+  private static final long INITIAL_RETRY_DELAY_MILLIS = 42l;
+  private static final long MAX_RETRY_DELAY_MILLIS = 100l;
 
   private static final RetryOption TOTAL_TIMEOUT =
-      RetryOption.totalTimeout(Duration.ofMillis(420L));
+      RetryOption.totalTimeoutDuration(Duration.ofMillis(TOTAL_TIMEOUT_MILLIS));
   private static final RetryOption INITIAL_RETRY_DELAY =
-      RetryOption.initialRetryDelay(Duration.ofMillis(42L));
+      RetryOption.initialRetryDelayDuration(Duration.ofMillis(INITIAL_RETRY_DELAY_MILLIS));
   private static final RetryOption RETRY_DELAY_MULTIPLIER = RetryOption.retryDelayMultiplier(1.5);
   private static final RetryOption MAX_RETRY_DELAY =
-      RetryOption.maxRetryDelay(Duration.ofMillis(100));
+      RetryOption.maxRetryDelayDuration(Duration.ofMillis(MAX_RETRY_DELAY_MILLIS));
   private static final RetryOption MAX_ATTEMPTS = RetryOption.maxAttempts(100);
   private static final RetryOption JITTERED = RetryOption.jittered(false);
 
   private static final RetrySettings retrySettings =
       RetrySettings.newBuilder()
-          .setTotalTimeout(Duration.ofMillis(420L))
-          .setInitialRetryDelay(Duration.ofMillis(42L))
+          .setTotalTimeoutDuration(Duration.ofMillis(420L))
+          .setInitialRetryDelayDuration(Duration.ofMillis(42L))
           .setRetryDelayMultiplier(1.5)
-          .setMaxRetryDelay(Duration.ofMillis(100))
+          .setMaxRetryDelayDuration(Duration.ofMillis(100))
           .setMaxAttempts(100)
           .setJittered(false)
           .build();
@@ -61,10 +64,10 @@ void testEqualsAndHashCode() {
     assertNotEquals(MAX_ATTEMPTS, MAX_RETRY_DELAY);
     assertNotEquals(JITTERED, MAX_ATTEMPTS);
 
-    RetryOption totalTimeout = RetryOption.totalTimeout(Duration.ofMillis(420L));
-    RetryOption initialRetryDelay = RetryOption.initialRetryDelay(Duration.ofMillis(42L));
+    RetryOption totalTimeout = RetryOption.totalTimeoutDuration(Duration.ofMillis(420L));
+    RetryOption initialRetryDelay = RetryOption.initialRetryDelayDuration(Duration.ofMillis(42L));
     RetryOption retryDelayMultiplier = RetryOption.retryDelayMultiplier(1.5);
-    RetryOption maxRetryDelay = RetryOption.maxRetryDelay(Duration.ofMillis(100));
+    RetryOption maxRetryDelay = RetryOption.maxRetryDelayDuration(Duration.ofMillis(100));
     RetryOption maxAttempts = RetryOption.maxAttempts(100);
     RetryOption jittered = RetryOption.jittered(false);
 
@@ -101,17 +104,17 @@ void testMergeToSettings() {
     assertEquals(retrySettings, mergedRetrySettings);
 
     defRetrySettings =
-        defRetrySettings.toBuilder().setTotalTimeout(Duration.ofMillis(420L)).build();
+        defRetrySettings.toBuilder().setTotalTimeoutDuration(Duration.ofMillis(420L)).build();
     mergedRetrySettings = RetryOption.mergeToSettings(defRetrySettings, TOTAL_TIMEOUT);
     assertEquals(defRetrySettings, mergedRetrySettings);
 
     defRetrySettings =
-        defRetrySettings.toBuilder().setMaxRetryDelay(Duration.ofMillis(100)).build();
+        defRetrySettings.toBuilder().setMaxRetryDelayDuration(Duration.ofMillis(100)).build();
     mergedRetrySettings = RetryOption.mergeToSettings(defRetrySettings, MAX_RETRY_DELAY);
     assertEquals(defRetrySettings, mergedRetrySettings);
 
     defRetrySettings =
-        defRetrySettings.toBuilder().setInitialRetryDelay(Duration.ofMillis(42L)).build();
+        defRetrySettings.toBuilder().setInitialRetryDelayDuration(Duration.ofMillis(42L)).build();
     mergedRetrySettings = RetryOption.mergeToSettings(defRetrySettings, INITIAL_RETRY_DELAY);
     assertEquals(defRetrySettings, mergedRetrySettings);
 
@@ -127,4 +130,20 @@ void testMergeToSettings() {
     mergedRetrySettings = RetryOption.mergeToSettings(defRetrySettings, JITTERED);
     assertEquals(defRetrySettings, mergedRetrySettings);
   }
+
+  @Test
+  public void threetenMethods_producesEquivalentJavaTimeRetryOptions() {
+
+    final RetryOption totalTimeoutThreeten =
+        RetryOption.totalTimeout(org.threeten.bp.Duration.ofMillis(TOTAL_TIMEOUT_MILLIS));
+    final RetryOption initialRetryDelayThreeten =
+        RetryOption.initialRetryDelay(
+            org.threeten.bp.Duration.ofMillis(INITIAL_RETRY_DELAY_MILLIS));
+    final RetryOption maxRetryDelayThreeten =
+        RetryOption.maxRetryDelay(org.threeten.bp.Duration.ofMillis(MAX_RETRY_DELAY_MILLIS));
+
+    assertEquals(TOTAL_TIMEOUT, totalTimeoutThreeten);
+    assertEquals(INITIAL_RETRY_DELAY, initialRetryDelayThreeten);
+    assertEquals(MAX_RETRY_DELAY, maxRetryDelayThreeten);
+  }
 }
diff --git a/java-core/google-cloud-core/src/test/java/com/google/cloud/SerializationTest.java b/java-core/google-cloud-core/src/test/java/com/google/cloud/SerializationTest.java
index 6c35c665b5..f591578f11 100644
--- a/java-core/google-cloud-core/src/test/java/com/google/cloud/SerializationTest.java
+++ b/java-core/google-cloud-core/src/test/java/com/google/cloud/SerializationTest.java
@@ -23,7 +23,7 @@
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import java.io.Serializable;
-import org.threeten.bp.Duration;
+import java.time.Duration;
 
 public class SerializationTest extends BaseSerializationTest {
 
@@ -37,7 +37,7 @@ public class SerializationTest extends BaseSerializationTest {
   private static final Role SOME_ROLE = Role.viewer();
   private static final Policy SOME_IAM_POLICY = Policy.newBuilder().build();
   private static final RetryOption CHECKING_PERIOD =
-      RetryOption.initialRetryDelay(Duration.ofSeconds(42));
+      RetryOption.initialRetryDelayDuration(Duration.ofSeconds(42));
   private static final LabelDescriptor LABEL_DESCRIPTOR =
       new LabelDescriptor("project_id", ValueType.STRING, "The project id");
   private static final MonitoredResourceDescriptor MONITORED_RESOURCE_DESCRIPTOR =
diff --git a/java-core/google-cloud-core/src/test/java/com/google/cloud/TimestampTest.java b/java-core/google-cloud-core/src/test/java/com/google/cloud/TimestampTest.java
index ba2ad5b701..110cd6b631 100644
--- a/java-core/google-cloud-core/src/test/java/com/google/cloud/TimestampTest.java
+++ b/java-core/google-cloud-core/src/test/java/com/google/cloud/TimestampTest.java
@@ -237,14 +237,75 @@ void parseTimestampWithoutTimeZoneOffset() {
 
   @Test
   void parseTimestampWithTimeZoneOffset() {
-    assertThat(Timestamp.parseTimestamp("0001-01-01T00:00:00-00:00"))
+    // Max values
+    assertThat(Timestamp.parseTimestampDuration("0001-01-01T00:00:00-00:00"))
         .isEqualTo(Timestamp.MIN_VALUE);
-    assertThat(Timestamp.parseTimestamp("9999-12-31T23:59:59.999999999-00:00"))
+    assertThat(Timestamp.parseTimestampDuration("9999-12-31T23:59:59.999999999-00:00"))
         .isEqualTo(Timestamp.MAX_VALUE);
-    assertThat(Timestamp.parseTimestamp("2020-12-06T19:21:12.123+05:30"))
+    // Extreme values (close to min/max)
+    assertThat(Timestamp.parseTimestampDuration("0001-01-01T00:00:00.000000001Z"))
+        .isEqualTo(Timestamp.ofTimeSecondsAndNanos(Timestamp.MIN_VALUE.getSeconds(), 1));
+    assertThat(Timestamp.parseTimestampDuration("9999-12-31T23:59:59.999999998Z"))
+        .isEqualTo(Timestamp.ofTimeSecondsAndNanos(Timestamp.MAX_VALUE.getSeconds(), 999999998));
+    // Common use cases
+    assertThat(Timestamp.parseTimestampDuration("2020-07-10T14:03:00-07:00"))
+        .isEqualTo(Timestamp.ofTimeSecondsAndNanos(1594414980, 0));
+    assertThat(Timestamp.parseTimestampDuration("2020-12-06T19:21:12.123+05:30"))
         .isEqualTo(Timestamp.ofTimeSecondsAndNanos(1607262672, 123000000));
-    assertThat(Timestamp.parseTimestamp("2020-07-10T14:03:00-07:00"))
+    // We also confirm that parsing a timestamp with nano precision will behave the same as the
+    // threeten counterpart
+    assertThat(Timestamp.parseTimestampDuration("2020-12-06T19:21:12.123+05:30"))
+        .isEqualTo(Timestamp.parseTimestamp("2020-12-06T19:21:12.123+05:30"));
+    // Timestamps with fractional seconds at nanosecond level
+    assertThat(Timestamp.parseTimestampDuration("2020-12-06T19:21:12.123456789+05:30"))
+        .isEqualTo(Timestamp.ofTimeSecondsAndNanos(1607262672, 123456789));
+    // Fractional seconds beyond nanos should throw an exception
+    assertThrows(
+        org.threeten.bp.format.DateTimeParseException.class,
+        //            DateTimeParseException.class,
+        () -> Timestamp.parseTimestampDuration("2020-12-06T19:21:12.123456789321+05:30"));
+    // Missing components (should throw exceptions)
+    assertThrows(
+        //            DateTimeParseException.class,
+        org.threeten.bp.format.DateTimeParseException.class,
+        () -> Timestamp.parseTimestampDuration("2020-12-06"));
+    // Whitespace should not be supported
+    assertThrows(
+        //            DateTimeParseException.class,
+        org.threeten.bp.format.DateTimeParseException.class,
+        () -> Timestamp.parseTimestampDuration("  2020-12-06T19:21:12.123+05:30  "));
+    // It should be case-insensitive
+    assertThat(Timestamp.parseTimestampDuration("2020-07-10t14:03:00-07:00"))
         .isEqualTo(Timestamp.ofTimeSecondsAndNanos(1594414980, 0));
+    // Invalid time zone offsets
+    assertThrows(
+        //            DateTimeParseException.class,
+        org.threeten.bp.format.DateTimeParseException.class,
+        () -> Timestamp.parseTimestampDuration("2020-12-06T19:21:12.123+25:00"));
+    assertThrows(
+        //            DateTimeParseException.class,
+        org.threeten.bp.format.DateTimeParseException.class,
+        () -> Timestamp.parseTimestampDuration("2020-12-06T19:21:12.123-25:00"));
+    // Int values for SecondOfMinute should be between 0 and 59
+    assertThrows(
+        //            DateTimeParseException.class,
+        org.threeten.bp.format.DateTimeParseException.class,
+        () -> Timestamp.parseTimestampDuration("2016-12-31T23:59:60Z"));
+  }
+
+  @Test
+  void parseTimestampWithZoneString() {
+    // Valid RFC 3339 timestamps with time zone names
+    assertThat(Timestamp.parseTimestampDuration("2020-12-06T08:51:12.123America/Toronto"))
+        .isEqualTo(Timestamp.ofTimeSecondsAndNanos(1607262672, 123000000));
+    assertThat(Timestamp.parseTimestampDuration("2023-04-10T22:42:10.123456789Europe/London"))
+        .isEqualTo(Timestamp.ofTimeSecondsAndNanos(1681162930, 123456789));
+
+    // Invalid time zone names
+    assertThrows(
+        org.threeten.bp.format.DateTimeParseException.class,
+        //            DateTimeParseException.class,
+        () -> Timestamp.parseTimestampDuration("2020-12-06T19:21:12.123Invalid/TimeZone"));
   }
 
   @Test
diff --git a/java-core/google-cloud-core/src/test/java/com/google/cloud/testing/BaseEmulatorHelperTest.java b/java-core/google-cloud-core/src/test/java/com/google/cloud/testing/BaseEmulatorHelperTest.java
index 79b58a83c9..beb6e68b85 100644
--- a/java-core/google-cloud-core/src/test/java/com/google/cloud/testing/BaseEmulatorHelperTest.java
+++ b/java-core/google-cloud-core/src/test/java/com/google/cloud/testing/BaseEmulatorHelperTest.java
@@ -16,6 +16,8 @@
 
 package com.google.cloud.testing;
 
+import static com.google.api.gax.util.TimeConversionUtils.toJavaTimeDuration;
+
 import com.google.api.client.util.Charsets;
 import com.google.cloud.ServiceOptions;
 import com.google.cloud.testing.BaseEmulatorHelper.EmulatorRunner;
@@ -28,12 +30,12 @@
 import java.net.URL;
 import java.net.URLConnection;
 import java.net.URLStreamHandler;
+import java.time.Duration;
 import java.util.List;
 import java.util.concurrent.TimeoutException;
 import java.util.logging.Logger;
 import org.easymock.EasyMock;
 import org.junit.jupiter.api.Test;
-import org.threeten.bp.Duration;
 
 class BaseEmulatorHelperTest {
 
@@ -71,8 +73,15 @@ public void start() throws IOException, InterruptedException {
     }
 
     @Override
-    public void stop(Duration timeout) throws IOException, InterruptedException, TimeoutException {
-      waitForProcess(timeout);
+    public void stop(org.threeten.bp.Duration timeout)
+        throws IOException, InterruptedException, TimeoutException {
+      stopDuration(toJavaTimeDuration(timeout));
+    }
+
+    @Override
+    public void stopDuration(Duration timeout)
+        throws IOException, InterruptedException, TimeoutException {
+      waitForProcessDuration(timeout);
     }
 
     @Override
@@ -91,13 +100,13 @@ void testEmulatorHelper() throws IOException, InterruptedException, TimeoutExcep
     emulatorRunner.start();
     EasyMock.expectLastCall();
     EasyMock.expect(emulatorRunner.getProcess()).andReturn(process);
-    emulatorRunner.waitFor(Duration.ofMinutes(1));
+    emulatorRunner.waitForDuration(Duration.ofMinutes(1));
     EasyMock.expectLastCall().andReturn(0);
     EasyMock.replay(process, emulatorRunner);
     TestEmulatorHelper helper =
         new TestEmulatorHelper(ImmutableList.of(emulatorRunner), BLOCK_UNTIL);
     helper.start();
-    helper.stop(Duration.ofMinutes(1));
+    helper.stopDuration(Duration.ofMinutes(1));
     EasyMock.verify();
   }
 
@@ -157,13 +166,13 @@ void testEmulatorHelperMultipleRunners()
     secondRunner.start();
     EasyMock.expectLastCall();
     EasyMock.expect(secondRunner.getProcess()).andReturn(process);
-    secondRunner.waitFor(Duration.ofMinutes(1));
+    secondRunner.waitForDuration(Duration.ofMinutes(1));
     EasyMock.expectLastCall().andReturn(0);
     EasyMock.replay(process, secondRunner);
     TestEmulatorHelper helper =
         new TestEmulatorHelper(ImmutableList.of(firstRunner, secondRunner), BLOCK_UNTIL);
     helper.start();
-    helper.stop(Duration.ofMinutes(1));
+    helper.stopDuration(Duration.ofMinutes(1));
     EasyMock.verify();
   }