As we look towards the future of optical communications, there are ever more missions requiring low size, weight, and power (SWaP), low cost, and very agile space terminals. Increased numbers of end-users look to minimize the costs associated with non-recurring engineering, and spacecraft operators that prefer not to deviate from their primary mission during communications operations. We present an optical terminal architecture which is specifically designed to have ready access to a greater-than-hemispherical field of regard (±175° in azimuth and ±120° in elevation, at up to 10°/sec slew rate), is modular to facilitate future technology upgrades and technology transfer to industry, can be scaled for use in LEO, GEO and deep-space applications, and leverages experience from a variety of successful space terminals that precede this design. In the past two years, this agile, modular, and scalable optical terminal architecture concept has been realized as a 10-cm aperture space terminal design. The terminal design was divided into subassemblies and further developed by industry partners, yielding an Engineering Development Unit (EDU) that has been assembled and tested. The optical and pointing performance of the EDU have been measured and are reported. Flight units of this 10-cm aperture space terminal are being developed for two upcoming missions, one for a LEO-based application and another for a lunar-based application, both presently scheduled for launch in 2021.