Rust has earned its reputation for improving memory-, type-, and thread-safety in systems software. But what happens when you use it in safety-critical settings? What about brown-field projects with lots of existing code in other languages? Or code that interacts with hardware, outside the purview of Rust’s Abstract Machine? In this talk we cover the gaps between Safe Rust and Unsafe Rust and the need for Safety-Critical Rust Coding Guidelines like those being developed by the Safety-Critical Rust Consortium.