Turbulence in the molecular interstellar medium

Star formation in galaxies occurs within the complex environments of giant molecular clouds. The efficiency of this process is necessarily regulated by the dynamics of the molecular gas. I will review the state of observations that have contributed to our understanding of turbulence within the molecular ISM and the relationship between gas dynamics and star formation. I will focus on spectroscopic measurements of molecular line emission, most notably, the low rotational transitions of ^12CO and ^13CO, and the analysis methods that assess the properties of turbulent gas flows (velocity structure function, intermittency, and driving scales). I will summarize the need for future observations that can further advance our understanding of this critical process.