diff --git a/BUILDING.md b/BUILDING.md
index ad3b374a1..ac9a2716f 100644
--- a/BUILDING.md
+++ b/BUILDING.md
@@ -18,6 +18,8 @@ To build the `containerd` daemon, and the `ctr` simple test client, the followin
 * Protoc 3.x compiler and headers (download at the [Google protobuf releases page](https://github.com/protocolbuffers/protobuf/releases))
 * Btrfs headers and libraries for your distribution. Note that building the btrfs driver can be disabled via the build tag `no_btrfs`, removing this dependency.
 
+> *Note*: On macOS, you need a third party runtime to run containers on containerd
+
 ## Build the development environment
 
 First you need to setup your Go development environment. You can follow this
@@ -58,6 +60,8 @@ the system, sometimes it is necessary to build runc directly when working with
 container runtime development. Make sure to follow the guidelines for versioning
 in [RUNC.md](/docs/RUNC.md) for the best results.
 
+> *Note*: Runc only supports Linux
+
 ## Build containerd
 
 `containerd` uses `make` to create a repeatable build flow. It means that you
@@ -121,6 +125,8 @@ Changes to these files should become a single commit for a PR which relies on ve
 
 Please refer to [RUNC.md](/docs/RUNC.md) for the currently supported version of `runc` that is used by containerd.
 
+> *Note*: On macOS, the containerd daemon can be built and run natively. However, as stated above, runc only supports linux.
+
 ### Static binaries
 
 You can build static binaries by providing a few variables to `make`: