There is generally limited consolidated documentation regarding how various elements of Swedish Armed Forces´ Defence Outlook Study are conducted and the methods used, which also applies to the first phase referred to as military strategic analysis (MSA). The purpose of this report is to record and share knowledge about the methods and approaches used during the MSA work in Defence Outlook Study 27 and the identified lessons of this work. The Defence Outlook Study follows essentially the same overarching process in 4-5 year cycle, but the content, methods, and ways of conducting the work in the different phases vary. The work begins with an MSA that forms the basis for concept development, which in turn forms the foundation for the creation of military structures as a basis for the Supreme Commander's military advice in preparation for defence decisions. The MSA phase in Defence Outlook 27 consisted of several different parts. The work started with horizon scanning and analysis of trends, including future technological developments, as well as an analysis of the future adversary. These inputs were then used to describe the future operating environment and ultimately identify the military problems that the Swedish Armed Forces will face in the future. Defence Outlook Study 27 has worked on the MSA during 2023-2024, and identified lessons from the work include, among other things, the conduct of the various parts and the internal work, external collaboration, and commitment among the primary stakeholders of the study. Several of the identified lessons are not only linked to the work on the MSA but also pertain to the study work in a more general sense.