A lot of comments that just seem to ignore the fact that noone would actually <i>want</i> standard collections to be thread safe! Concurrent collections are <i>slow</i>. That&#x27;s why class libraries use <i>different types</i> for a therad safe collection and a regular non-thread safe collection. If you are using concurrency you have to use concurrent collections.<p>You could argue that if most Go code is concurrent then the <i>regular</i> collections should be the thread safe ones, and for code that is known to be single threaded there would be simpler&#x2F;faster non-concurrent collections. That is a completely valid argument to make, but I think that design would be too confusing for new Go developers, since in most other languages the standard collections are the non-concurrent ones, and the concurrent ones are special, and it&#x27;s an explicit design goal of Go to be easy to adopt coming from another language.