Efficient non spatial and spatial simulation of biochemical reaction networks The dissertation is focused on algorithms for performing non spatial and spatial stochastic simulations of reaction networks and on the exploration of improved or alternative approaches. Central topics are the evaluation and a subsequent comparison of algorithm performance in terms of execution speed and accuracy the extension of temporal leap methods to the spatial realm as well as the introduction of a variant for a parallel execution and the realization of a multi algorithm simulation which introduces inter rules to forge a link between the synchronized execution of subsidiary algorithms.