This European Standard contains a glossary of terms, which can contribute to the conditions for free competition and a level playing field for engineering services providers in Europe in regard to industrial products. This European Standard deals with the intellectual services necessary to transform needs into practical solutions from their conception, through realisation to operation and during the life cycle of a working product such as buildings, industrial products etc. The terminology aims at facilitating the cooperation between partners in the field of Engineering Services (ES). Its structure is based on stages in the life cycle of an industrial product. It is not a description of the contents of the tasks to be executed, neither on their scheduling, nor on the actors concerned who depend on the national context, the clients, type and importance of the product and its environment. The major terms are defined covering the lifecycle of industrial products. These terms are applicable to all sectors, for example: aerospace, automotive, capital equipment.