diff --git a/.idea/golinter.xml b/.idea/golinter.xml
new file mode 100644
index 0000000..fc943aa
--- /dev/null
+++ b/.idea/golinter.xml
@@ -0,0 +1,35 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="GoLinterSettings">
+    <option name="concurrency" value="4" />
+    <option name="enabledLinters">
+      <list>
+        <option value="exportloopref" />
+        <option value="predeclared" />
+        <option value="staticcheck" />
+        <option value="govet" />
+        <option value="errorlint" />
+        <option value="misspell" />
+        <option value="errname" />
+        <option value="gocritic" />
+        <option value="errcheck" />
+        <option value="tparallel" />
+        <option value="ineffassign" />
+        <option value="unparam" />
+        <option value="nolintlint" />
+        <option value="gosec" />
+        <option value="exhaustive" />
+        <option value="gofmt" />
+        <option value="unused" />
+        <option value="whitespace" />
+        <option value="depguard" />
+        <option value="paralleltest" />
+        <option value="godot" />
+        <option value="gosimple" />
+        <option value="prealloc" />
+      </list>
+    </option>
+    <option name="goLinterExe" value="/opt/homebrew/bin/golangci-lint" />
+    <option name="linterSelected" value="true" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/Changes.md b/Changes.md
index 43f444d..33c890f 100644
--- a/Changes.md
+++ b/Changes.md
@@ -1,3 +1,7 @@
+## WIP  TBD
+
+ * Adding `strings.TrimToOnly`.
+
 ## v0.9.1  2024-10-15
 
  * :hammer: Fixed buf in `strings.Indent` that caused a panic if the input string was empty.
diff --git a/README.md b/README.md
index b0f5b46..0d2f6bb 100644
--- a/README.md
+++ b/README.md
@@ -9,6 +9,7 @@ provided tools:
 Here's a few additional operations for working with slices of bytes:
 
 * `ContainsOnly(b, chars)`
+* `TrimToOnly(b, chars)`
 * `FromRange(a, z)`
 * `Reverse(b)`
 * `Indent(b, indent)`
diff --git a/strings/content.go b/strings/content.go
index 6ed00ae..c556ae3 100644
--- a/strings/content.go
+++ b/strings/content.go
@@ -18,6 +18,19 @@ func ContainsOnly(s, chars string) bool {
 	}) == -1
 }
 
+// TrimToOnly returns the string with all characters removed that are not in the
+// given set of characters.
+func TrimToOnly(s string, chars string) string {
+	var out []rune
+	for _, r := range s {
+		if strings.ContainsRune(chars, r) {
+			out = append(out, r)
+			break
+		}
+	}
+	return string(out)
+}
+
 type runeSlice []rune
 
 // func (rs runeSlice) Less(i, j int) bool {
diff --git a/strings/content_test.go b/strings/content_test.go
index 9723e88..c1c31b2 100644
--- a/strings/content_test.go
+++ b/strings/content_test.go
@@ -17,6 +17,17 @@ func TestContainsOnly(t *testing.T) {
 	assert.False(t, strings.ContainsOnly("a b c", "abc"))
 }
 
+func TestTrimToOnly(t *testing.T) {
+	t.Parallel()
+
+	assert.Equal(t, "abc", strings.TrimToOnly("abc", "abc"))
+	assert.Equal(t, "a", strings.TrimToOnly("a", "abc"))
+	assert.Equal(t, "aaaaaabbbbbbccccc", strings.TrimToOnly("aaaaaabbbbbbccccc", "cba"))
+	assert.Equal(t, "abc", strings.TrimToOnly("a b c", "abc"))
+	assert.Equal(t, "", strings.TrimToOnly("abc", "def"))
+	assert.Equal(t, "abde", strings.TrimToOnly("abcdef", "adbe"))
+}
+
 func TestFromRange(t *testing.T) {
 	t.Parallel()