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We re-examine critically the observational evidence that has been used to support either turbulence-induced or ambipolar-diffusion-initiated fragmentation of molecular clouds and the subsequent collapse of fragments to form stars. The relevant observations include, but are not limited to, the ages of T-Tauri stars, age spreads of stars in clusters, statistics of both pre-stellar cores as well as of clouds with and without embedded stars, CO and H-alpha emission in other galaxies, linewidth-size relations, Zeeman observations, density and velocity structures in clouds and cores, mass-to-flux ratios, etc. Time permitting, recent numerical simulations will also be presented. Myths are separated from reality, and suggestions for further observational tests of the two ideas are made.
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