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The role played by magnetic fields in the star formation process - from formation of molecular clouds, through their fragmentation and collapse of fragments, to the evolution of protostars and bipolar outflows - is a fundamental question of star formation studies. One of the most important aspects of this question is the formation of cores and their support against gravity. The two major classes of star formation theory differ in the role played by magnetic fields. The strong field models have magnetic fields controlling the formation and evolution of the molecular clouds from which stars form, with ambipolar diffusion driving the formation of cores and their gravitational collapse to form protostars. The weak field models have turbulent flows controlling the formation of clouds and cores, with cores either dissipating back into the general interstellar medium or collapsing and forming stars if they are self-gravitating when formed. Triggered star formation generally falls into this second class of star formation theory. In this talk I will describe the current state of observations that may discriminate between these two extreme-case models of star formation and discuss the results. I will end by discussing prospects for further progress in the coming era of powerful new telescopes.
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