In a cellular mobile network, high traffic areas often account for a large proportion of the total traffic in the network. Improving the customer experience in those areas is a constant challenge for Mobile Operators. New small cells are often the solution in those areas but increasing the performance of the macro cells is also a key strategy in the Operator arsenal. Massive MIMO is a relatively new base station solution for both 4G and 5G networks. This talk will cover the fundamentals of massive MIMO, how massive MIMO can be deployed in mobile networks, the challenges, examples of technical solutions and some of the initial results of this new technology.