For the past decade or more MIMO systems have been the subject of very intensive research. For example, it was one of the most important topics in the previous COST Wireless Action, COST 231. However in the past few years, in the time-frame of COST 2100 these techniques have begun to be implemented in practice. In particular they have appeared in the standards for next generation systems such as LTE, 3GPP-LTE Advanced (LTE-Adv) and WiMAX, as well as the latest versions of WiFi. This chapter brings together the MIMO systems used in next generation systems with other work on the implementation and simulation of these systems. It also describes advances in MIMO techniques in a number of areas. The first section is divided into two sub-sections dealing first with simulators and testbeds which are used in system-level simulators to evaluate overall system capacity, as discussed in later chapters of this book. Secondly the development of terminals for next generation MIMO systems is considered, especially considering the additional RF hardware required for MIMO. Section 7.2 then discusses especially precoding techniques used in many of the recent standards to implement MIMO. In particular precoding allows the implementation of closed loop or adaptive MIMO. In next generation systems there is also much increased attention on MU-MIMO and on multi-terminal MIMO in general, including so-called “network MIMO” approaches, which appear in LTE as Coordinated Multiple Point (CoMP): this is covered in Sect. 7.3. Various advanced MIMO transmission and detection approaches are covered in Sects. 7.4 to 7.6, including some interesting work on MIMO techniques involving Continuous Phase Modulation (CPM), giving advantages in terms of Peak-to-Average Power Ratio (PAPR).