In this paper I look at a number of issue surrounding the question of the title. I will begin with a report of a recent paper by Beckman et al where they examine the issue of a certain type of locality and differentiate it from the idea of causality (no "faster than light" signaling), and show that, surprisingly, the former is slighlty more restrictive than the latter. I then discuss H. Stapp's argument that one can demonstrate the non-locality of Quantum mechanics by showing that one obtains a contradiction with th predictions of quantum mechanics if one assumes that quantum mechanics is local, and that certain counterfactual lines of argument are valid. Finally I conclude with a statement of my position that quantum mechanics is local, presenting a simple field theoretic analysis of a Bell type experiment. Using this I argue that the quantum correlations present in such a Bell experiment are the result of a common cause, just as they are in the case of classical correlations.
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