A spacecraft is a machine that is created to fly in the outer space. There are numerous purposes for which spacecrafts are used, such as space colonization, communications, meteorology, navigation, transportation, Earth observation, etc. There are two types of spacecrafts crewed and unmanned. Spacecraft engineering is a branch of engineering that deals with the development and creation of spacecraft. The designing of spacecraft involves various technological and engineering disciplines such as aerodynamics, propulsion, avionics, materials science, manufacturing and structural analysis. The interaction between these technologies is known as spacecraft engineering. Some of the elements of spacecraft engineering include astrodynamics, aircraft structures, aeroelasticity, fluid mechanics, aeroacoustics, etc. This book contains some path-breaking studies in the field of spacecraft engineering. It is a compilation of chapters that discuss the most vital concepts and emerging trends in the field of spacecraft engineering. This book is appropriate for students seeking detailed information in this area as well as for expert.