Three collocated Doppler Wind Lidars (DWLs) were used to measure winds during a demonstration campaign in New Hampshire September 2000. Corresponding line-of-sight (LOS) velocities determined by pairs of DWLs realized good agreement under clear sky conditions with random differences that increase as a function of decreasing signal strength. The radiosonde wind component projected along the DWL LOS typically showed good agreement. Clouds caused sharp attenuation of the signal and adversely affected LOS retrievals at cloud levels and beyond. Implications of the results for improving the instruments and organizing future Doppler wind lidar field campaigns are discussed.