We survey recent developments in off-beam cloud lidar and especially the Wide Angle Imaging Lidar (WAIL) developed at Los Alamos National Laboratory (LANL). By abandoning the single backscattering assumption of standard (on-beam) lidar in favor of a multiple scattering model and with the appropriate modifications of the instrument, we enable detection robust detection of the cloud boundary opposite to the source, hence cloud thickness (as well as altitude). We can also determine a volumeaveraged extinction at 532 nm, hence mean cloud optical depth. Comparisons with Atmospheric Radiation Measurement (ARM) program instruments targeting the same cloud properties are already good and easily improvable. Finally, we describe several extensions of WAIL capability at various stages of planning and realization. Off-Beam Cloud Lidar Concept and Designs The principle of off-beam lidar operation is predicated on the fact that multiply-scattered light starting and ending at a cloud boundary thoroughly samples the interior of a dense non-absorbing medium (Davis et al. 1997). So, if an optically thick cloud is targeted, the characteristics of the reflected radiance distribution in space, angle and time will depend on its optical and geometrical properties. Photons should be collected within a receiver field of view (FOV) wide enough to take in essentially th
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