Mutexes provide mutual exclusion to prevent race conditions in concurrent Go programs. The sync.Mutex type uses atomic operations to ensure only one goroutine accesses shared resources at a time. The Lock() method acquires the mutex using atomic compare-and-swap operations, while Unlock() releases it. Using defer with Unlock() prevents deadlocks from forgotten unlocks. Mutexes work best for low-contention scenarios; high contention may require alternatives like sync.RWMutex or channels.