A system and method of parallelizing programs assigns write tokens and read tokens to data objects accessed by computational operations. During run time, the write sets and read sets for computational operations are resolved and the computational operations executed only after they have obtained the necessary tokens for data objects corresponding to the resolved write and read sets. A data object may have unlimited read tokens but only a single write token and the write token may be released only if no read tokens are outstanding. Data objects provide a wait list which serves as an ordered queue for computational operations waiting for tokens.