It will block your process (just like a `receive' does), but a good Erlang/OTP system is generally comprised of a great many processes. If one process can block

It will block your process (just like a `receive' does), but a good Erlang/OTP system is generally comprised of a great many processes. If one process can block, your design is wrong, and the system itself is designed to be robust when things block like this. You expect your processes to be blocked, but you design things so that truly concurrent activities are being run in parallel.