An analysis of laser action in a multielement resonator structure is presented. Resonance wavelengths, threshold gains, energy density distributions, and quality of the modes are obtained from a linear model. A multimode rate equation approach then describes the dynamical behavior and gives absolute values for the modal output. It is shown that structures with only a few active elements can have a high mode selectivity providing single‐longitudinal‐mode operation of semiconductor lasers under high‐frequency current modulation. For example, the suppression of unwanted secondary modes in an eight‐element laser can be larger than 23 dB.