We introduce explicit fusions of names. To `fuse' two names is to declare that they may be used interchangeably. An explicit fusion is one that can exist in parallel with some other process, allowing us to ask for instance how a process might behave in a context where x = y. We present the F -calculus, a simple process calculus with explicit fusions. It is similar in many respects to the fusion calculus but has a simple local reaction relation. We give embeddings of the -calculus and the fusion calculus. We provide a bisimulation congruence for theF -calculus and compare it with hyper-equivalence in the fusion calculus.