The Moon has been a focus for exploration since the early days of the space age. Recent updates to US space priorities have brought new focus to the Moon and cislunar space, along with plans to return humans to the Moon, establish crewed lunar outposts, and advance economic development in the cislunar regime. This course covers the fundamentals of space systems engineering as applied to lunar and cislunar missions. Topics include the science, exploration, economic, and security drivers of cislunar missions and implications for mission requirements; unique aspects of the lunar and cislunar environment and associated considerations for engineering spacecraft and payloads; cislunar astrodynamics and applications to cislunar mission design; case studies of current and future cislunar missions; and technology to enable future cislunar endeavors.