**Abstract**

This chapter focuses on the importance and need to focus much more strongly on the social and behavioral sciences, humanities, and arts regarding the study of space issues, and Mars issues specifically. The particular focus here deals with the vital need to balance planning for Martian settlements between the two major branches of science [i.e., (1) the physical and natural sciences plus the STEM disciplines and fields and (2) the social sciences, humanities, and arts]. The current focus on settling Mars is on transportation issues and physical infrastructure construction of habitats or cities. In contrast, the arguments made here support the idea that planning for Martian settlements must include the "other" branch of science, and this extends to the monitoring of social interactions and other forces associated with the complexities generated by a growing population existing in an isolated and dangerous ecosystem on another planet. On Earth, the social sciences are vital and they will be on Mars as well. Astrosociology is a multidisciplinary academic field that studies issues related to space exploration, settlement, and other issues from social-scientific perspective, and it is complementary to the so-called "hard" sciences. Collaboration on a much more extensive basis is already overdue.

**Keywords:** astrosociology, astrosocial phenomena, social sciences, humanities, arts, Mars, settlement
