diff --git a/Ghidra/Debug/Debugger-gadp/src/test/java/ghidra/dbg/gadp/GadpClientServerTest.java b/Ghidra/Debug/Debugger-gadp/src/test/java/ghidra/dbg/gadp/GadpClientServerTest.java
index fd3ee528d8..921158b544 100644
--- a/Ghidra/Debug/Debugger-gadp/src/test/java/ghidra/dbg/gadp/GadpClientServerTest.java
+++ b/Ghidra/Debug/Debugger-gadp/src/test/java/ghidra/dbg/gadp/GadpClientServerTest.java
@@ -364,8 +364,10 @@ public class GadpClientServerTest implements AsyncTestUtils {
 		public TestGadpTargetMethod(TestTargetObject<?, ?> parent, String key) {
 			super(parent.getModel(), parent, key, "Method");
 
-			setAttributes(Map.of(PARAMETERS_ATTRIBUTE_NAME, PARAMS, RETURN_TYPE_ATTRIBUTE_NAME,
-				Integer.class), "Initialized");
+			setAttributes(Map.of(
+				PARAMETERS_ATTRIBUTE_NAME, PARAMS,
+				RETURN_TYPE_ATTRIBUTE_NAME, Integer.class),
+				"Initialized");
 		}
 
 		@Override
@@ -381,6 +383,37 @@ public class GadpClientServerTest implements AsyncTestUtils {
 		}
 	}
 
+	private static final TargetParameterMap ORDERED_PARAMS = TargetMethod.makeParameters(
+		ParameterDescription.create(String.class, "H", true, "", "H", "H"),
+		ParameterDescription.create(String.class, "e", true, "", "e", "e"),
+		ParameterDescription.create(String.class, "l", true, "", "l", "l"),
+		ParameterDescription.create(String.class, "m", true, "", "l", "l"),
+		ParameterDescription.create(String.class, "o", true, "", "o", "o"),
+		ParameterDescription.create(String.class, "W", true, "", "W", "W"),
+		ParameterDescription.create(String.class, "p", true, "", "o", "o"),
+		ParameterDescription.create(String.class, "r", true, "", "r", "r"),
+		ParameterDescription.create(String.class, "n", true, "", "l", "l"),
+		ParameterDescription.create(String.class, "d", true, "", "d", "d"));
+
+	public class TestGadpTargetMethodWithManyParameters
+			extends TestTargetObject<TargetObject, TestTargetObject<?, ?>> implements TargetMethod {
+
+		public TestGadpTargetMethodWithManyParameters(TestTargetObject<?, ?> parent, String key) {
+			super(parent.getModel(), parent, key, "MethodPlus");
+
+			setAttributes(Map.of(
+				PARAMETERS_ATTRIBUTE_NAME, ORDERED_PARAMS,
+				RETURN_TYPE_ATTRIBUTE_NAME, Integer.class),
+				"Initialized");
+		}
+
+		@Override
+		public CompletableFuture<Object> invoke(Map<String, ?> arguments) {
+			fail("I wasn't expecting that");
+			return AsyncUtils.nil();
+		}
+	}
+
 	@TargetObjectSchemaInfo(name = "ProcessContainer")
 	public class TestGadpTargetProcessContainer
 			extends TestTargetObject<TestGadpTargetProcess, TestGadpTargetSession>
@@ -473,8 +506,10 @@ public class GadpClientServerTest implements AsyncTestUtils {
 		public TestGadpTargetAvailableContainer(TestGadpTargetSession session) {
 			super(session.getModel(), session, "Available", "AvailableContainer");
 
-			setAttributes(List.of(new TestGadpTargetMethod(this, "greet")), Map.of(),
-				"Initialized");
+			setAttributes(List.of(
+				new TestGadpTargetMethod(this, "greet"),
+				new TestGadpTargetMethodWithManyParameters(this, "bigGreet")),
+				Map.of(), "Initialized");
 		}
 
 		@Override
@@ -815,6 +850,32 @@ public class GadpClientServerTest implements AsyncTestUtils {
 		}
 	}
 
+	@Test
+	public void testMethodParametersOrderPreserved() throws Throwable {
+		AsynchronousSocketChannel socket = socketChannel();
+		try (ServerRunner runner = new ServerRunner()) {
+			GadpClient client = new GadpClient("Test", socket);
+			waitOn(AsyncUtils.completable(TypeSpec.VOID, socket::connect,
+				runner.server.getLocalAddress()));
+			waitOn(client.connect());
+			TargetObject greet =
+				waitOn(client.fetchModelObject(PathUtils.parse("Available.bigGreet")));
+			assertTrue(greet.getInterfaceNames().contains("Method"));
+			TargetMethod method = greet.as(TargetMethod.class);
+
+			TargetParameterMap params = method.getParameters();
+			assertEquals(ORDERED_PARAMS, params);
+
+			assertEquals("HelmoWprnd",
+				params.values().stream().map(p -> p.name).collect(Collectors.joining()));
+
+			waitOn(client.close());
+		}
+		finally {
+			socket.close();
+		}
+	}
+
 	@Test
 	public void testListRoot() throws Throwable {
 		AsynchronousSocketChannel socket = socketChannel();
diff --git a/Ghidra/Debug/Framework-Debugging/src/main/java/ghidra/dbg/target/TargetMethod.java b/Ghidra/Debug/Framework-Debugging/src/main/java/ghidra/dbg/target/TargetMethod.java
index 2647535b3d..e6e723b137 100644
--- a/Ghidra/Debug/Framework-Debugging/src/main/java/ghidra/dbg/target/TargetMethod.java
+++ b/Ghidra/Debug/Framework-Debugging/src/main/java/ghidra/dbg/target/TargetMethod.java
@@ -201,7 +201,10 @@ public interface TargetMethod extends TargetObject {
 	 * @return a map of descriptions by name
 	 */
 	static TargetParameterMap makeParameters(Stream<ParameterDescription<?>> params) {
-		return TargetParameterMap.copyOf(params.collect(Collectors.toMap(p -> p.name, p -> p)));
+		return TargetParameterMap
+				.copyOf(params.collect(Collectors.toMap(p -> p.name, p -> p, (a, b) -> {
+					throw new IllegalArgumentException("duplicate parameters: " + a + " and " + b);
+				}, LinkedHashMap::new)));
 	}
 
 	/**
diff --git a/Ghidra/Debug/Framework-Debugging/src/main/java/ghidra/dbg/util/CollectionUtils.java b/Ghidra/Debug/Framework-Debugging/src/main/java/ghidra/dbg/util/CollectionUtils.java
index 5487e92800..d80f13b855 100644
--- a/Ghidra/Debug/Framework-Debugging/src/main/java/ghidra/dbg/util/CollectionUtils.java
+++ b/Ghidra/Debug/Framework-Debugging/src/main/java/ghidra/dbg/util/CollectionUtils.java
@@ -204,7 +204,7 @@ public enum CollectionUtils {
 		protected final Map<K, V> wrapped;
 
 		public AbstractNMap(Map<K, V> map) {
-			this.wrapped = Map.copyOf(map);
+			this.wrapped = Collections.unmodifiableMap(new LinkedHashMap<>(map));
 		}
 
 		@Override