diff --git a/Package.swift b/Package.swift
index 49f678e..374b35b 100644
--- a/Package.swift
+++ b/Package.swift
@@ -22,7 +22,10 @@ let package = Package(
     targets: [
         .target(
             name: "AX",
-            dependencies: []),
+            dependencies: []/*,
+            swiftSettings: [
+                .enableExperimentalFeature("StrictConcurrency")
+            ]*/),
         .executableTarget(
             name: "ObserverExample",
             dependencies: ["AX"]),
diff --git a/Sources/AX/AX.swift b/Sources/AX/AX.swift
index d806501..2d30179 100644
--- a/Sources/AX/AX.swift
+++ b/Sources/AX/AX.swift
@@ -24,12 +24,16 @@ public func isTrusted() -> Bool {
 ///
 /// See also `public func AXIsProcessTrustedWithOptions(_ options: CFDictionary?) -> Bool`
 @available(macOS 10.9, *)
+@Sendable
 public func isTrusted(promptIfNeeded: Bool) -> Bool {
     AXIsProcessTrustedWithOptions(optionsDictionary(promptIfNeeded: promptIfNeeded))
 }
+private struct AXKey: Sendable {
+    static let trustedCheckOptionPrompt = kAXTrustedCheckOptionPrompt.takeUnretainedValue()
+}
 private func optionsDictionary(promptIfNeeded: Bool) -> CFDictionary {
     guard promptIfNeeded else {
         return [CFString:CFTypeRef]() as CFDictionary
     }
-    return [kAXTrustedCheckOptionPrompt.takeUnretainedValue():kCFBooleanTrue] as CFDictionary
+    return [AXKey.trustedCheckOptionPrompt:kCFBooleanTrue] as CFDictionary
 }
diff --git a/Sources/AX/AXError.swift b/Sources/AX/AXError.swift
index 402f67c..d6b8bb3 100644
--- a/Sources/AX/AXError.swift
+++ b/Sources/AX/AXError.swift
@@ -10,7 +10,7 @@ import ApplicationServices.HIServices
 // but we want to drop the `success` case
 
 @available(macOS 10.2, *)
-public enum AXError: Error {
+public enum AXError: Error, Sendable {
     /// The action is not supported by the UIElement.
     case actionUnsupported
     /// The accessibility API is disabled.
diff --git a/Sources/AX/AXObserver.swift b/Sources/AX/AXObserver.swift
index 739b74b..90f612f 100644
--- a/Sources/AX/AXObserver.swift
+++ b/Sources/AX/AXObserver.swift
@@ -9,7 +9,7 @@ import Foundation
 import AppKit
 
 @available(macOS 10.2, *)
-public struct Observer: CustomStringConvertible, CustomDebugStringConvertible {
+public struct Observer: @unchecked Sendable, CustomStringConvertible, CustomDebugStringConvertible {
 
     // MARK: Init
 
diff --git a/Sources/AX/AXTextMarker.swift b/Sources/AX/AXTextMarker.swift
index 1ab53cf..a7fbca3 100644
--- a/Sources/AX/AXTextMarker.swift
+++ b/Sources/AX/AXTextMarker.swift
@@ -8,7 +8,7 @@ import ApplicationServices
 import Cocoa
 
 @available(macOS 11, *)
-public struct TextMarker: CustomStringConvertible, CustomDebugStringConvertible {
+public struct TextMarker: @unchecked Sendable, CustomStringConvertible, CustomDebugStringConvertible {
 
     // MARK: Init
 
@@ -51,7 +51,7 @@ public struct TextMarker: CustomStringConvertible, CustomDebugStringConvertible
 }
 
 @available(macOS 11, *)
-public struct TextMarkerRange: CustomStringConvertible, CustomDebugStringConvertible {
+public struct TextMarkerRange: @unchecked Sendable, CustomStringConvertible, CustomDebugStringConvertible {
 
     // MARK: Init
 
diff --git a/Sources/AX/AXUIElement.swift b/Sources/AX/AXUIElement.swift
index af4e4e4..315357e 100644
--- a/Sources/AX/AXUIElement.swift
+++ b/Sources/AX/AXUIElement.swift
@@ -5,11 +5,10 @@
 //
 
 import AppKit
-import ApplicationServices
-import Cocoa
+@preconcurrency import ApplicationServices
 
 @available(macOS 10.0, *)
-public struct UIElement: CustomStringConvertible, CustomDebugStringConvertible {
+public struct UIElement: Sendable, CustomStringConvertible, CustomDebugStringConvertible {
 
     // MARK: Init
 
diff --git a/Sources/AX/AXValue.swift b/Sources/AX/AXValue.swift
index 1d20a6e..7e1645e 100644
--- a/Sources/AX/AXValue.swift
+++ b/Sources/AX/AXValue.swift
@@ -8,7 +8,7 @@ import ApplicationServices
 import Cocoa
 
 @available(macOS 10.11, *)
-public enum Value: Equatable {
+public enum Value: Equatable, Sendable {
     case point(CGPoint)
     case size(CGSize)
     case rect(CGRect)