Abstract: An abradable fluid seal for use in the space between two relatively movable members, such as the space between the cylindrical path of the rotating blade tips in an aircraft gas turbine and the surrounding stationary casing of the turbine. The preferred seal uses a series of thin narrow elongate metal strips. These are assembled and secured in side-by-side relationship to form a flexible integrated assembly having, in the direction of its thickness, an outer base portion and an inner seal portion. Each strip has corresponding base and seal portions and, over a given length, a corresponding succession of undulations in each portion.