diff --git a/objc2/Cargo.toml b/objc2/Cargo.toml
index 896d7091a..9ad78c840 100644
--- a/objc2/Cargo.toml
+++ b/objc2/Cargo.toml
@@ -42,6 +42,7 @@ unstable_autoreleasesafe = []
 
 [dependencies]
 malloc_buf = { version = "1.0", optional = true }
+terminated = "1.0"
 objc-sys = { path = "../objc-sys", version = "=0.2.0-alpha.1" }
 objc2-encode = { path = "../objc2-encode", version = "=2.0.0-beta.2" }
 
diff --git a/objc2/examples/introspection.rs b/objc2/examples/introspection.rs
index 5a10b2736..403e779e7 100644
--- a/objc2/examples/introspection.rs
+++ b/objc2/examples/introspection.rs
@@ -1,4 +1,5 @@
 use core::ptr::NonNull;
+use terminated::ntstr;
 
 use objc2::rc::{Id, Owned};
 use objc2::runtime::{Class, Object};
@@ -30,7 +31,7 @@ fn main() {
 
     // Access an ivar of the object
     // TODO: Fix this!
-    let isa: *const Class = unsafe { *obj.ivar("isa") };
+    let isa: *const Class = unsafe { *obj.ivar(ntstr!("isa")) };
     println!("NSObject isa: {:?}", isa);
 
     #[cfg(feature = "malloc")]
diff --git a/objc2/src/declare.rs b/objc2/src/declare.rs
index c5128d7e5..7e28b81cf 100644
--- a/objc2/src/declare.rs
+++ b/objc2/src/declare.rs
@@ -13,16 +13,17 @@
 //! use objc2::{class, sel};
 //! use objc2::declare::ClassDecl;
 //! use objc2::runtime::{Class, Object, Sel};
+//! use terminated::ntstr;
 //!
 //! let superclass = class!(NSObject);
-//! let mut decl = ClassDecl::new("MyNumber", superclass).unwrap();
+//! let mut decl = ClassDecl::new(ntstr!("MyNumber"), superclass).unwrap();
 //!
 //! // Add an instance variable
-//! decl.add_ivar::<u32>("_number");
+//! decl.add_ivar::<u32>(ntstr!("_number"));
 //!
 //! // Add an ObjC method for getting the number
 //! extern "C" fn my_number_get(this: &Object, _cmd: Sel) -> u32 {
-//!     unsafe { *this.ivar("_number") }
+//!     unsafe { *this.ivar(ntstr!("_number")) }
 //! }
 //! unsafe {
 //!     decl.add_method(
@@ -40,6 +41,9 @@ use core::mem;
 use core::mem::ManuallyDrop;
 use core::ptr;
 use std::ffi::CString;
+use std::os::raw::c_char;
+
+use terminated::NulTerminatedStr;
 
 use crate::runtime::{Bool, Class, Imp, Object, Protocol, Sel};
 use crate::{ffi, Encode, EncodeArguments, Encoding, Message};
@@ -138,10 +142,10 @@ unsafe impl Send for ClassDecl {}
 unsafe impl Sync for ClassDecl {}
 
 impl ClassDecl {
-    fn with_superclass(name: &str, superclass: Option<&Class>) -> Option<ClassDecl> {
-        let name = CString::new(name).unwrap();
+    fn with_superclass(name: &NulTerminatedStr, superclass: Option<&Class>) -> Option<ClassDecl> {
+        let name_ptr = name.as_ptr() as *const c_char;
         let super_ptr = superclass.map_or(ptr::null(), |c| c) as _;
-        let cls = unsafe { ffi::objc_allocateClassPair(super_ptr, name.as_ptr(), 0) };
+        let cls = unsafe { ffi::objc_allocateClassPair(super_ptr, name_ptr, 0) };
         if cls.is_null() {
             None
         } else {
@@ -153,7 +157,7 @@ impl ClassDecl {
     ///
     /// Returns [`None`] if the class couldn't be allocated, or a class with
     /// that name already exist.
-    pub fn new(name: &str, superclass: &Class) -> Option<ClassDecl> {
+    pub fn new(name: &NulTerminatedStr, superclass: &Class) -> Option<ClassDecl> {
         ClassDecl::with_superclass(name, Some(superclass))
     }
 
@@ -171,7 +175,10 @@ impl ClassDecl {
     /// the entire `NSObject` protocol is implemented.
     /// Functionality it expects, like implementations of `-retain` and
     /// `-release` used by ARC, will not be present otherwise.
-    pub fn root(name: &str, intitialize_fn: extern "C" fn(&Class, Sel)) -> Option<ClassDecl> {
+    pub fn root(
+        name: &NulTerminatedStr,
+        intitialize_fn: extern "C" fn(&Class, Sel),
+    ) -> Option<ClassDecl> {
         let mut decl = ClassDecl::with_superclass(name, None);
         if let Some(ref mut decl) = decl {
             unsafe {
@@ -261,15 +268,15 @@ impl ClassDecl {
     /// # Panics
     ///
     /// If the ivar wasn't successfully added.
-    pub fn add_ivar<T: Encode>(&mut self, name: &str) {
-        let c_name = CString::new(name).unwrap();
+    pub fn add_ivar<T: Encode>(&mut self, name: &NulTerminatedStr) {
+        let name_ptr = name.as_ptr() as *const c_char;
         let encoding = CString::new(T::ENCODING.to_string()).unwrap();
         let size = mem::size_of::<T>();
         let align = log2_align_of::<T>();
         let success = Bool::from_raw(unsafe {
             ffi::class_addIvar(
                 self.cls as _,
-                c_name.as_ptr(),
+                name_ptr,
                 size,
                 align,
                 encoding.as_ptr(),
@@ -322,9 +329,9 @@ impl ProtocolDecl {
     /// Constructs a [`ProtocolDecl`] with the given name.
     ///
     /// Returns [`None`] if the protocol couldn't be allocated.
-    pub fn new(name: &str) -> Option<ProtocolDecl> {
-        let c_name = CString::new(name).unwrap();
-        let proto = unsafe { ffi::objc_allocateProtocol(c_name.as_ptr()) } as *mut Protocol;
+    pub fn new(name: &NulTerminatedStr) -> Option<ProtocolDecl> {
+        let name_ptr = name.as_ptr() as *const c_char;
+        let proto = unsafe { ffi::objc_allocateProtocol(name_ptr) } as *mut Protocol;
         if proto.is_null() {
             None
         } else {
diff --git a/objc2/src/rc/id.rs b/objc2/src/rc/id.rs
index 44ecc956f..45f660ec3 100644
--- a/objc2/src/rc/id.rs
+++ b/objc2/src/rc/id.rs
@@ -62,8 +62,9 @@ use crate::Message;
 /// use objc2::msg_send;
 /// use objc2::runtime::{Class, Object};
 /// use objc2::rc::{Id, Owned, Shared, WeakId};
+/// use terminated::ntstr;
 ///
-/// let cls = Class::get("NSObject").unwrap();
+/// let cls = Class::get(ntstr!("NSObject")).unwrap();
 /// let obj: Id<Object, Owned> = unsafe {
 ///     Id::new(msg_send![cls, new])
 /// };
diff --git a/objc2/src/runtime.rs b/objc2/src/runtime.rs
index 3ce337187..3fd32c4f8 100644
--- a/objc2/src/runtime.rs
+++ b/objc2/src/runtime.rs
@@ -11,9 +11,11 @@ use core::ptr;
 use core::str;
 #[cfg(feature = "malloc")]
 use malloc_buf::Malloc;
-use std::ffi::{CStr, CString};
+use std::ffi::CStr;
+use std::os::raw::c_char;
 #[cfg(feature = "malloc")]
 use std::os::raw::c_uint;
+use terminated::NulTerminatedStr;
 
 pub use super::bool::Bool;
 use crate::{ffi, Encode, Encoding, RefEncode};
@@ -96,10 +98,10 @@ pub type Imp = unsafe extern "C" fn();
 impl Sel {
     /// Registers a method with the Objective-C runtime system,
     /// maps the method name to a selector, and returns the selector value.
-    pub fn register(name: &str) -> Self {
-        let name = CString::new(name).unwrap();
+    pub fn register(name: &NulTerminatedStr) -> Self {
+        let name_ptr = name.as_ptr() as *const c_char;
         Self {
-            ptr: unsafe { ffi::sel_registerName(name.as_ptr()) },
+            ptr: unsafe { ffi::sel_registerName(name_ptr) },
         }
     }
 
@@ -252,10 +254,10 @@ impl Class {
 
     /// Returns the class definition of a specified class, or [`None`] if the
     /// class is not registered with the Objective-C runtime.
-    pub fn get(name: &str) -> Option<&'static Self> {
-        let name = CString::new(name).unwrap();
+    pub fn get(name: &NulTerminatedStr) -> Option<&'static Self> {
+        let name_ptr = name.as_ptr() as *const c_char;
         unsafe {
-            let cls = ffi::objc_getClass(name.as_ptr());
+            let cls = ffi::objc_getClass(name_ptr);
             if cls.is_null() {
                 None
             } else {
@@ -335,10 +337,10 @@ impl Class {
 
     /// Returns the ivar for a specified instance variable of self, or
     /// [`None`] if self has no ivar with the given name.
-    pub fn instance_variable(&self, name: &str) -> Option<&Ivar> {
-        let name = CString::new(name).unwrap();
+    pub fn instance_variable(&self, name: &NulTerminatedStr) -> Option<&Ivar> {
+        let name_ptr = name.as_ptr() as *const c_char;
         unsafe {
-            let ivar = ffi::class_getInstanceVariable(self.as_ptr(), name.as_ptr());
+            let ivar = ffi::class_getInstanceVariable(self.as_ptr(), name_ptr);
             if ivar.is_null() {
                 None
             } else {
@@ -358,9 +360,9 @@ impl Class {
     }
 
     #[allow(unused)]
-    fn class_variable(&self, name: &str) -> Option<&Ivar> {
-        let name = CString::new(name).unwrap();
-        let ivar = unsafe { ffi::class_getClassVariable(self.as_ptr(), name.as_ptr()) };
+    fn class_variable(&self, name: &NulTerminatedStr) -> Option<&Ivar> {
+        let name_ptr = name.as_ptr() as *const c_char;
+        let ivar = unsafe { ffi::class_getClassVariable(self.as_ptr(), name_ptr) };
         // SAFETY: TODO
         unsafe { ivar.cast::<Ivar>().as_ref() }
     }
@@ -439,10 +441,10 @@ impl Protocol {
 
     /// Returns the protocol definition of a specified protocol, or [`None`]
     /// if the protocol is not registered with the Objective-C runtime.
-    pub fn get(name: &str) -> Option<&'static Protocol> {
-        let name = CString::new(name).unwrap();
+    pub fn get(name: &NulTerminatedStr) -> Option<&'static Protocol> {
+        let name_ptr = name.as_ptr() as *const c_char;
         unsafe {
-            let proto = ffi::objc_getProtocol(name.as_ptr());
+            let proto = ffi::objc_getProtocol(name_ptr);
             if proto.is_null() {
                 None
             } else {
@@ -517,7 +519,7 @@ impl UnwindSafe for Protocol {}
 impl RefUnwindSafe for Protocol {}
 // Note that Unpin is not applicable.
 
-fn ivar_offset<T: Encode>(cls: &Class, name: &str) -> isize {
+fn ivar_offset<T: Encode>(cls: &Class, name: &NulTerminatedStr) -> isize {
     match cls.instance_variable(name) {
         Some(ivar) => {
             assert!(T::ENCODING.equivalent_to_str(ivar.type_encoding()));
@@ -549,7 +551,7 @@ impl Object {
     /// The caller must ensure that the ivar is actually of type `T`.
     ///
     /// Library implementors should expose a safe interface to the ivar.
-    pub unsafe fn ivar<T: Encode>(&self, name: &str) -> &T {
+    pub unsafe fn ivar<T: Encode>(&self, name: &NulTerminatedStr) -> &T {
         let offset = ivar_offset::<T>(self.class(), name);
         // `offset` is given in bytes, so we convert to `u8`
         let ptr = self as *const Self as *const u8;
@@ -569,7 +571,7 @@ impl Object {
     /// The caller must ensure that the ivar is actually of type `T`.
     ///
     /// Library implementors should expose a safe interface to the ivar.
-    pub unsafe fn ivar_mut<T: Encode>(&mut self, name: &str) -> &mut T {
+    pub unsafe fn ivar_mut<T: Encode>(&mut self, name: &NulTerminatedStr) -> &mut T {
         let offset = ivar_offset::<T>(self.class(), name);
         // `offset` is given in bytes, so we convert to `u8`
         let ptr = self as *mut Self as *mut u8;
@@ -589,7 +591,7 @@ impl Object {
     /// The caller must ensure that the ivar is actually of type `T`.
     ///
     /// Library implementors should expose a safe interface to the ivar.
-    pub unsafe fn set_ivar<T: Encode>(&mut self, name: &str, value: T) {
+    pub unsafe fn set_ivar<T: Encode>(&mut self, name: &NulTerminatedStr, value: T) {
         // SAFETY: Invariants upheld by caller
         unsafe { *self.ivar_mut::<T>(name) = value };
     }
@@ -635,10 +637,12 @@ mod tests {
     use crate::test_utils;
     use crate::Encode;
 
+    use terminated::ntstr;
+
     #[test]
     fn test_ivar() {
         let cls = test_utils::custom_class();
-        let ivar = cls.instance_variable("_foo").unwrap();
+        let ivar = cls.instance_variable(ntstr!("_foo")).unwrap();
         assert_eq!(ivar.name(), "_foo");
         assert!(<u32>::ENCODING.equivalent_to_str(ivar.type_encoding()));
         assert!(ivar.offset() > 0);
@@ -650,7 +654,7 @@ mod tests {
     #[test]
     fn test_method() {
         let cls = test_utils::custom_class();
-        let sel = Sel::register("foo");
+        let sel = Sel::register(ntstr!("foo"));
         let method = cls.instance_method(sel).unwrap();
         assert_eq!(method.name().name(), "foo");
         assert_eq!(method.arguments_count(), 2);
@@ -671,7 +675,7 @@ mod tests {
         assert!(cls.instance_size() > 0);
         assert!(cls.superclass().is_none());
 
-        assert_eq!(Class::get(cls.name()), Some(cls));
+        assert_eq!(Class::get(ntstr!("CustomObject")), Some(cls));
 
         let metaclass = cls.metaclass();
         // The metaclass of a root class is a subclass of the root class
@@ -733,8 +737,8 @@ mod tests {
         let mut obj = test_utils::custom_object();
         assert_eq!(obj.class(), test_utils::custom_class());
         let result: u32 = unsafe {
-            obj.set_ivar("_foo", 4u32);
-            *obj.ivar("_foo")
+            obj.set_ivar(ntstr!("_foo"), 4u32);
+            *obj.ivar(ntstr!("_foo"))
         };
         assert_eq!(result, 4);
     }
diff --git a/objc2/src/test_utils.rs b/objc2/src/test_utils.rs
index 12f44d82a..6a0ce0960 100644
--- a/objc2/src/test_utils.rs
+++ b/objc2/src/test_utils.rs
@@ -1,6 +1,7 @@
 use core::ops::{Deref, DerefMut};
 use std::os::raw::c_char;
 use std::sync::Once;
+use terminated::ntstr;
 
 use crate::declare::{ClassDecl, ProtocolDecl};
 use crate::runtime::{Class, Object, Protocol, Sel};
@@ -75,20 +76,21 @@ pub(crate) fn custom_class() -> &'static Class {
         // The runtime will call this method, so it has to be implemented
         extern "C" fn custom_obj_class_initialize(_this: &Class, _cmd: Sel) {}
 
-        let mut decl = ClassDecl::root("CustomObject", custom_obj_class_initialize).unwrap();
+        let mut decl =
+            ClassDecl::root(ntstr!("CustomObject"), custom_obj_class_initialize).unwrap();
         let proto = custom_protocol();
 
         decl.add_protocol(proto);
-        decl.add_ivar::<u32>("_foo");
+        decl.add_ivar::<u32>(ntstr!("_foo"));
 
         extern "C" fn custom_obj_set_foo(this: &mut Object, _cmd: Sel, foo: u32) {
             unsafe {
-                this.set_ivar::<u32>("_foo", foo);
+                this.set_ivar::<u32>(ntstr!("_foo"), foo);
             }
         }
 
         extern "C" fn custom_obj_get_foo(this: &Object, _cmd: Sel) -> u32 {
-            unsafe { *this.ivar::<u32>("_foo") }
+            unsafe { *this.ivar::<u32>(ntstr!("_foo")) }
         }
 
         extern "C" fn custom_obj_get_struct(_this: &Object, _cmd: Sel) -> CustomStruct {
@@ -106,7 +108,7 @@ pub(crate) fn custom_class() -> &'static Class {
 
         extern "C" fn custom_obj_set_bar(this: &mut Object, _cmd: Sel, bar: u32) {
             unsafe {
-                this.set_ivar::<u32>("_foo", bar);
+                this.set_ivar::<u32>(ntstr!("_foo"), bar);
             }
         }
 
@@ -146,7 +148,7 @@ pub(crate) fn custom_protocol() -> &'static Protocol {
     static REGISTER_CUSTOM_PROTOCOL: Once = Once::new();
 
     REGISTER_CUSTOM_PROTOCOL.call_once(|| {
-        let mut decl = ProtocolDecl::new("CustomProtocol").unwrap();
+        let mut decl = ProtocolDecl::new(ntstr!("CustomProtocol")).unwrap();
 
         decl.add_method_description::<(i32,), ()>(sel!(setBar:), true);
         decl.add_method_description::<(), *const c_char>(sel!(getName), false);
@@ -155,7 +157,7 @@ pub(crate) fn custom_protocol() -> &'static Protocol {
         decl.register();
     });
 
-    Protocol::get("CustomProtocol").unwrap()
+    Protocol::get(ntstr!("CustomProtocol")).unwrap()
 }
 
 pub(crate) fn custom_subprotocol() -> &'static Protocol {
@@ -163,7 +165,7 @@ pub(crate) fn custom_subprotocol() -> &'static Protocol {
 
     REGISTER_CUSTOM_SUBPROTOCOL.call_once(|| {
         let super_proto = custom_protocol();
-        let mut decl = ProtocolDecl::new("CustomSubProtocol").unwrap();
+        let mut decl = ProtocolDecl::new(ntstr!("CustomSubProtocol")).unwrap();
 
         decl.add_protocol(super_proto);
         decl.add_method_description::<(u32,), u32>(sel!(calculateFoo:), true);
@@ -171,7 +173,7 @@ pub(crate) fn custom_subprotocol() -> &'static Protocol {
         decl.register();
     });
 
-    Protocol::get("CustomSubProtocol").unwrap()
+    Protocol::get(ntstr!("CustomSubProtocol")).unwrap()
 }
 
 pub(crate) fn custom_object() -> CustomObject {
@@ -183,7 +185,7 @@ pub(crate) fn custom_subclass() -> &'static Class {
 
     REGISTER_CUSTOM_SUBCLASS.call_once(|| {
         let superclass = custom_class();
-        let mut decl = ClassDecl::new("CustomSubclassObject", superclass).unwrap();
+        let mut decl = ClassDecl::new(ntstr!("CustomSubclassObject"), superclass).unwrap();
 
         extern "C" fn custom_subclass_get_foo(this: &Object, _cmd: Sel) -> u32 {
             let foo: u32 = unsafe { msg_send![super(this, custom_class()), foo] };