This paper presents the research which is carried out in the field of adaptive structures at the Institute for Lightweight Structures at the University of Stuttgart. The application of adaptive systems in the field of architecture and structural engineering creates new chances to design lightweight structures. Different concepts of active control can be used to manipulate the forces, the deflections and the vibration of structures. These concepts are categorised into two groups: control of external loads and control of internal forces. Active shape control can be used to reduce the external wind load by changing the shape of the cross-section of wide-span bridges or high-rise towers. Alternatively active force and/ or stiffness control can be used to manipulate the internal flow of forces and stresses in structures. Systems with active force control superimpose the actively generated forces with the already existing forces, while systems with active stiffness control redistribute the forces according to their varying stiffness distribution. The authors use active elements with variable length and/ or stiffness in static indeterminate structures to control the deflections and redistribute the forces. A bridge with actively controlled elements is presented, where the stress peaks can be reduced and a homogenisation of the force distribution can be obtained.