diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 39ff86ae0..e150e8659 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -154,7 +154,7 @@ jobs:
       # Use --no-fail-fast, except with dinghy
       TESTARGS: ${{ matrix.dinghy && ' ' || '--no-fail-fast' }} ${{ matrix.test-args }}
       FEATURES: ${{ matrix.features || 'malloc,block,exception,catch_all,verify_message' }}
-      UNSTABLE_FEATURES: ${{ matrix.unstable-features || 'unstable-autoreleasesafe' }}
+      UNSTABLE_FEATURES: ${{ matrix.unstable-features || 'unstable-autoreleasesafe,unstable-id-fundamental' }}
 
     runs-on: ${{ matrix.os }}
 
diff --git a/objc2-foundation/examples/basic_usage.rs b/objc2-foundation/examples/basic_usage.rs
index e1fd02f39..261fc0d7c 100644
--- a/objc2-foundation/examples/basic_usage.rs
+++ b/objc2-foundation/examples/basic_usage.rs
@@ -1,4 +1,4 @@
-use objc2::rc::autoreleasepool;
+use objc2::rc::{autoreleasepool, Id};
 use objc2_foundation::{NSArray, NSCopying, NSDictionary, NSObject, NSString};
 
 fn main() {
@@ -14,14 +14,14 @@ fn main() {
 
     // Create an NSArray from a Vec
     let objs = vec![obj, obj2];
-    let array = NSArray::from_vec(objs);
+    let array: Id<NSArray<_, _>, _> = objs.into();
     for obj in array.iter() {
         println!("{:?}", obj);
     }
     println!("{}", array.len());
 
     // Turn the NSArray back into a Vec
-    let mut objs = NSArray::into_vec(array);
+    let mut objs = Vec::from(array);
     let obj = objs.pop().unwrap();
 
     // Create an NSString from a str slice
diff --git a/objc2-foundation/src/array.rs b/objc2-foundation/src/array.rs
index 42aaa287a..f3eb8ffe1 100644
--- a/objc2-foundation/src/array.rs
+++ b/objc2-foundation/src/array.rs
@@ -215,6 +215,37 @@ impl<T: Message> DefaultId for NSArray<T, Shared> {
     }
 }
 
+impl<T: Message, O: Ownership> From<Id<NSArray<T, O>, Owned>> for Vec<Id<T, O>> {
+    fn from(array: Id<NSArray<T, O>, Owned>) -> Self {
+        let vec: Vec<&T> = (&*array).into();
+        vec.into_iter()
+            .map(|obj| unsafe { Id::retain(obj.into()) })
+            .collect()
+    }
+}
+
+impl<T: Message, O: Ownership> From<Vec<Id<T, O>>> for Id<NSArray<T, O>, Owned> {
+    fn from(vec: Vec<Id<T, O>>) -> Self {
+        unsafe { from_refs(vec.as_slice_ref()) }
+    }
+}
+
+impl<'a, T: Message, O: Ownership> From<&'a NSArray<T, O>> for Vec<&'a T> {
+    fn from(array: &'a NSArray<T, O>) -> Self {
+        array.objects_in_range(0..array.count())
+    }
+}
+
+impl<T: Message> From<&'_ NSArray<T, Shared>> for Vec<Id<T, Shared>> {
+    fn from(array: &NSArray<T, Shared>) -> Self {
+        array
+            .objects_in_range(0..array.count())
+            .into_iter()
+            .map(|obj| unsafe { Id::retain(obj.into()) })
+            .collect()
+    }
+}
+
 impl<T: Message, O: Ownership> NSMutableArray<T, O> {
     unsafe_def_fn!(pub fn new -> Owned);
 
@@ -378,6 +409,12 @@ impl<T: Message, O: Ownership> DefaultId for NSMutableArray<T, O> {
     }
 }
 
+impl<T: Message, O: Ownership> From<Vec<Id<T, O>>> for Id<NSMutableArray<T, O>, Owned> {
+    fn from(vec: Vec<Id<T, O>>) -> Self {
+        unsafe { from_refs(vec.as_slice_ref()) }
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use alloc::format;
@@ -395,7 +432,7 @@ mod tests {
         for _ in 0..len {
             vec.push(NSObject::new());
         }
-        NSArray::from_vec(vec)
+        vec.into()
     }
 
     fn sample_number_array(len: u8) -> Id<NSArray<NSValue<u8>, Shared>, Shared> {
@@ -517,7 +554,7 @@ mod tests {
     fn test_into_vec() {
         let array = sample_array(4);
 
-        let vec = NSArray::into_vec(array);
+        let vec = Vec::from(array);
         assert_eq!(vec.len(), 4);
     }
 
@@ -566,7 +603,7 @@ mod tests {
     #[test]
     fn test_sort() {
         let strings = vec![NSString::from_str("hello"), NSString::from_str("hi")];
-        let mut strings = NSMutableArray::from_vec(strings);
+        let mut strings: Id<NSMutableArray<_, _>, Owned> = strings.into();
 
         autoreleasepool(|pool| {
             strings.sort_by(|s1, s2| s1.as_str(pool).len().cmp(&s2.as_str(pool).len()));
diff --git a/objc2-foundation/src/enumerator.rs b/objc2-foundation/src/enumerator.rs
index 4f6415f32..f3b081547 100644
--- a/objc2-foundation/src/enumerator.rs
+++ b/objc2-foundation/src/enumerator.rs
@@ -167,13 +167,16 @@ impl<'a, C: NSFastEnumeration + ?Sized> Iterator for NSFastEnumerator<'a, C> {
 
 #[cfg(test)]
 mod tests {
+    use alloc::vec::Vec;
+    use objc2::rc::Id;
+
     use super::NSFastEnumeration;
     use crate::{NSArray, NSValue};
 
     #[test]
     fn test_enumerator() {
-        let vec = (0usize..4).map(NSValue::new).collect();
-        let array = NSArray::from_vec(vec);
+        let vec: Vec<_> = (0usize..4).map(NSValue::new).collect();
+        let array: Id<NSArray<_, _>, _> = vec.into();
 
         let enumerator = array.iter();
         assert_eq!(enumerator.count(), 4);
@@ -184,8 +187,8 @@ mod tests {
 
     #[test]
     fn test_fast_enumerator() {
-        let vec = (0usize..4).map(NSValue::new).collect();
-        let array = NSArray::from_vec(vec);
+        let vec: Vec<_> = (0usize..4).map(NSValue::new).collect();
+        let array: Id<NSArray<_, _>, _> = vec.into();
 
         let enumerator = array.iter_fast();
         assert_eq!(enumerator.count(), 4);
diff --git a/objc2/Cargo.toml b/objc2/Cargo.toml
index 49c10ad14..9a0199144 100644
--- a/objc2/Cargo.toml
+++ b/objc2/Cargo.toml
@@ -40,6 +40,9 @@ malloc = ["malloc_buf"]
 # Uses nightly features to make AutoreleasePool zero-cost even in debug mode
 unstable-autoreleasesafe = []
 
+# Marks `rc::Id` with nightly `fundamental` feature.
+unstable-id-fundamental = []
+
 # Runtime selection. See `objc-sys` for details.
 apple = ["objc-sys/apple"]
 gnustep-1-7 = ["objc-sys/gnustep-1-7"]
diff --git a/objc2/src/lib.rs b/objc2/src/lib.rs
index ad14b3b71..6416d688e 100644
--- a/objc2/src/lib.rs
+++ b/objc2/src/lib.rs
@@ -168,6 +168,7 @@
     feature = "unstable-autoreleasesafe",
     feature(negative_impls, auto_traits)
 )]
+#![cfg_attr(feature = "unstable-id-fundamental", feature(fundamental))]
 #![warn(elided_lifetimes_in_paths)]
 #![warn(missing_docs)]
 #![deny(non_ascii_idents)]
diff --git a/objc2/src/rc/id.rs b/objc2/src/rc/id.rs
index 2acd4b960..9f13a4fb0 100644
--- a/objc2/src/rc/id.rs
+++ b/objc2/src/rc/id.rs
@@ -96,6 +96,7 @@ use crate::Message;
 /// let cloned: Id<T, Shared> = shared.clone();
 /// // Do something with `&T` here
 /// ```
+#[cfg_attr(feature = "unstable-id-fundamental", fundamental)]
 #[repr(transparent)]
 // TODO: Figure out if `Message` bound on `T` would be better here?
 // TODO: Add `ptr::Thin` bound on `T` to allow for only extern types