Modern technology without lasers is hardly to be imagined. Due to technological progresses in manufacturing, quality, and width of applications they have successfully entered the field of optical online and inline process analytical instrumentation. Opportunities by application of laser-based methods for gas analysis will be demonstrated in the field of infrared spectroscopy and Raman spectroscopy (vibrational spectroscopy). Using Raman spectroscopy in hollow-core photonic crystal fibers low gas concentrations can be detected with measurement times of a few seconds. Using quantum cascade lasers trace methane emissions indicating a potential leakage can be detected from a distance and by applying lasers and nonlinear optical components, highly sensitive and fast infrared detectors operating at room temperature for gas analysis can be realized.