The objectives of this study are to define the fundamental notions of collaboration in design field. The results of this study are summarized as follows: Firstly, collaboration means a cooperative work which are cooperatively done by collabarator and collaboratee on the equal status within a certain period of time, based on core ability of each of them. This cooperative work is presented with a visual image based on the identity of participants, and it creates an added value. Collaboration is different from convergence and hybrid in the methodological aspects and from brand alliance and strategic alliance in the aspects of the subject of project. Secondly, collaboration has been developing through step of using the specific ability, step of sharing each core abilities, and step of fusing their identities, in a view of the sphere of cooperative work and the intimate relations in reciprocity. Thirdly, according to strategic purpose, collaboration can be classified into value ascending collaboration, image changing collaboration, business-field extension collaboration, and event collaboration. Fourthly, production methods of collaboration consist of limited edition method, premium line method, common line method, producing a collaborative product, and so on. Fifthly, differentiation effect, image upgrade effect, production of higher value-added products, sale increase, diversification of business, sharing the targets, and promotion effect are achievable through collaboration. Sixthly, to make progress in collaboration successfully, the compatibility of combination between collaborator and collaboratee, the superiority of collaboratee, definitude of collaboration, the fit method of collaboration, the novelty of collatoration, possibility of issuing of collaboration, and perfection of collabo-product must be the points which deserve our attention.