This article presents an overview of developments at IMST in the area of antenna front-ends for mobile satellite terminals. Such type of antennas has become a key area of interest because of the ever growing multimedia services provided over wireless links and satellites. Various activities in this area have been conducted in the past, and are on-going. Antenna front-ends for mobile platforms are, in general, complex systems because they have to incorporate special features in order to perform beam steering, and at the same time also be cost-effective. The complexity of the antenna systems, developed at IMST, ranges from small arrays with switch-able elements and partially mechanically and electronically steerable arrays (hybrid systems) to fully electronically steerable arrays. This article examines which kind of user requirements for the three basic mobile platforms (land, maritime and aeronautical) exist, and what kind of impact they have on the design of the front-ends. Latter aspect is critical to achieve a cost-effective design. This is illustrated by examples from past and on-going projects in L-, Ku-, and K/Ka-band. Different concepts are presented and key aspects discussed.