In a world where much of society is dependent on digital infrastructure, various cyber threats can pose a great risk to businesses, critical infrastructure and potentially entire nations. For this reason, research and education as well as the preparation of strategies,  training of personnel etc., is imperative. Cyber ranges can provide ''safe environments'' in which for example cyber security exercises and experiments can be conducted. While easier to deploy and configure than ''real'' infrastructures, monitoring of such environments during ongoing exercises/experiments poses a number of challenges. During this thesis work, the question of what types of data and information could be relevant to provide in a monitoring system for this context was investigated, with regard to aspects such as providing technical support or gaining situational awareness during exercises. Results gained from a survey with participants from relevant organizations, contributed greatly to this question. The survey and literature study also provided insights into challenges and potential problems of developing and running such monitoring. CRATE is a cyber range developed and maintained by the Swedish Defence Research Agency (FOI). In this thesis work, some of the challenges and potential problems found are tackled with a suggested design and an implemented monitoring system prototype for CRATE. Apart from providing functionality to retrieve information about accounts and privileges as well as status of services, the design of the prototype also lays the foundation for a flexible and extensible monitoring system -- fully adapted for use within a cyber range. With cyber exercises becoming both more prevalent and extensive, the need for capable monitoring of exercise environments will naturally arise. While the developed prototype may facilitate future cyber exercises/experiments in CRATE, the results of this thesis work are also ready to be used as a source of inspiration for other cyber range operators.