MIMO (multiple-input multiple-output) radar refers to an architecture that employs multiple, spatially distributed or colocated transmitters and receivers. The widely spaced antenna structure suggests unique features that set MIMO radar apart from other radar systems, making it strongly related to MIMO communications. The widely separated transmit/receive antennas capture different aspects of the target cross section that can be exploited to obtain diversity gain for detection and estimation of the target's various parameters, such as angle of arrival, and Doppler. The use of coherent processing can provide localization accuracy gains well beyond that supported by the radar's waveform. This paper provides a review of some recent work on computing the Cramer-Rao lower bound (CRLB) on the achievable localization accuracy. The geometric dilution of precision (GDOP) is used as a tool for assessing and illustrating the localization accuracy of the Best Linear Unbiased Estimator (BLUE).