Clouds play vitally important roles in climate and water resources by virtue of their ability to transform radiant energy and water phase in the atmosphere. In the last decade, significant remote sensing advances have opened avenues for unprecedented ground-based measurements of cloud properties and processes. This article describes a small, integrated assembly of active and passive remote sensors, designed for that purpose. This cloud research package includes an 8-mm-wavelength "cloud" radar, a dual-frequency microwave radiometer, and a narrow-band infrared radiometer. These instruments operate unattended within a standard sea container. Simultaneous data from the instruments are merged to provide measurements of numerous features of the clouds overhead. These include measurements of cloud macro-structure, such as layer heights and thicknesses, and estimates of microphysical properties, including vertical profiles of hydrometeor mean size, total concentration, and mass content. Continuous measurements of liquid water path, water vapor path, surface pressure, temperature and humidity and, in some situations, cloud base temperature are also obtained. The heart of the system is the low-power but high-sensitivity cloud radar that can detect nearly all visible clouds overhead, including situations involving multiple layers and optically dense clouds that optical sensors cannot penetrate. The radar is identical to those designed by NOAA/ETL for a decade of unattended operations at the U.S. Department of Energy's Cloud and Radiation Testbed sites. This transportable radar/radiometer package, however, is intended for shorter-term deployments at various field experiment locations. Thus far in its brief history, it has been used for cloud studies in Colorado, Massachusetts, and onboard research ships in the Arctic, Indian, and Pacific Oceans. Applications of the multi-sensor package include research to assess the impact of clouds on climate change, aviation safety, radio communications, and use as an anchor-point data source for calibrating and validating satellite-based retrievals of cloud properties.