Business and Mission critical communications (MCC) is a major communication paradigm that is used by public agencies, e.g., during emergency situations, or critical infrastructure companies, e.g., airports, transportation, etc. MCC are conveyed by dedicated Private Mobile Radio (PMR) networks that offer a group (or multicast) communication service. This is a one-to-many or many-to-many communication, and it is one of the essential features of the PMR networks to manage teams of employees. In 5G New Radio, group communication will be supported for MCC from 3GPP Release R17 onwards. Due to the critical aspects of their missions, MCC has very stringent requirements in terms of reliability, coverage and should offer secure, group communications. This talk will discuss the design of robust, reliable, and secured physical layer multi-input-multi-output (MIMO) transceivers for MCC while highlighting the accompanying challenges to adhere to the requirements of critical services. Coordinated multimedia Multicast/Broadcast single frequency network (MBSFN) is considered a potential technology for MCC as it benefits from increased coverage and inter-cell interference mitigation. In this context, MIMO multimedia MBSFN system design is presented wherein each base station (BS) of a coordinated cluster multicasts a common message to all the users in a group. The cluster of synchronized BSs is dynamically selected for optimal utilization of resources within an MBSFN, which further enhances the overall performance at the system level. Furthermore, as the channel state information (CSI) is never perfectly known at the transmitter and receiver node, the transceiver matrices that are resilient to channel errors should be designed. Finally, this talk will discuss the need for incorporating MIMO beamforming, multicasting, physical layer security, robustness towards CSI errors, and dynamic clustering to obtain optimal transceivers for MCC. Through numerical results, the efficacy of the optimally developed MCC system is demonstrate.