A number of young stars, like FU Orionis, have been observed to experience short abrupt changes in their luminosity of an order of magnitude or more. These changes are commonly attributed to episodic fluctuations in the accretion rate onto the star. However, the characteristics, frequency and importance of these bursts in the star formation process are poorly constrained. Recently, episodic accretion has been proposed as the origin of the stellar age spread in low-mass stars inferred in young clusters. Episodic accretion has also been suggested as a solution for the protostellar "luminosity problem," wherein protostars are observed to be dimmer than predicted by star formation models. In this talk, I will give an overview of each of these issues and evaluate whether episodic accretion could provide a solution. I will also discuss some current and future observational programs that may help to constrain protostellar accretion histories.
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