A uniform theory of conditionals is one which compositionally captures the behavior of both indicative and subjunctive conditionals without positing implausible ambiguities. This paper raises several new problems for the leading uniform analysis (Stalnaker 1975) and develops a new theory which solves them. I also show that this new analysis provides an improved treatment of three much-discussed phenomena (the import-export equivalence, reverse Sobel-sequences and disjunctive antecedents). While these results concern central issues in the study of conditionals, broader themes in the philosophy of language and formal semantics are also engaged here. This new analysis exploits a dynamic conception of meaning where the meaning of a symbol is its potential to change an agent's mental state (or the state of a conversation) rather than being the symbol's content (e.g. the proposition it expresses). The analysis of conditionals is also built on the idea that the contrast between subjunctive and indicative conditionals parallels the contrast between revising and consistently extending one's beliefs.