The interior spaces depend, in their design, on thought and its novelties, since thought is changeable with the change of human nature and its levels, with the change of time and place, and with the change of events, there for; thought finds a place within the melting pot of influence, to be influenced and keeping up. Thought with all of what it carries of accumulations of knowledge, it makes its role clearly in the mind of designer and his culture and environment and that makes him to have an area of creativity and innovation and leaving the familiar things, innovating distinct things, imposing changes, displacing fixed things, and to clarify this essential joint, we decided to study the concept of thought when it establishes its pioneering as a reference or a contemporary event through diagnosis of the problem of research revolving on the lack of a study specific to the pioneering thought especially in the modern interior design. The communication with the pioneering intellectual references (modernism and after that) requires crystallizing its concepts with the contemporary technological developments because the contemporary interior design doesn't separate in any form from the references that formed its turn in the reality of world interior designs. Problem: (Does the pioneering thought embody in the contemporary design of interior spaces? Does the pioneering thought depend on the principles and styles that have pioneering and intellectual references? Does it give birth to new connections adding to those references contemporary directions?). Objective: manifested in revealing the pioneering thought in the contemporary designs of interior space and in diagnosis its intellectual references and cognitive connections in the light of contemporary directions. Moreover, the importance of research contributes in establishing a primary information base searching in the developments of cognitive design awareness for the thought of design and the necessity of adopting the pioneering thought from it in designing the contemporary interior spaces. Background: 1-The first one includes the general approach of pioneering thought that follows in the direction of establishing the thought whose pioneering is crystallized through the designer's effort as well as keeping on the objective factors that consider progressive and civilized trend. 2-The second one deals with the pioneering thought in the interior design in which the interior space is an essential topic and a practical field representing a practical application of this thought. Procedures: depended on the descriptive methodology in analysis. A sample selected purposely from the population of research. It included applied selected fields of interior space design from the architects of interior space for example the architect "Le Corbusier" and the architect " Zuha Hadid". These designs are distributed in Europe. Results: 1-The contemporary thought is a phenomenon in itself. It established its entity from the mixing of synchronous pioneering intellectual references which are various in the way of their application and it made a change in the paths and a critical transformation in the intellectual position of the contemporary interior designer. 2-The pioneering thought in the design of the interior spaces classified according to the levels of influence. They may have intensive effect that leads to a big stride in the design or they may be a simple contribution that makes some of them classified within the field of pioneering products. Recommendation and suggestions for future researches are given that may contribute in enriching the scientific knowledge for the pioneering thought. A bibliography for the sources and references of this research is mentioned