With a starting point in defining space through materials, colours, planes, and surfaces, the aim of the work presented in this thesis was to explore and introduce spatial concepts as design variables in textile design. Another aim was to explore surface patterns in terms of their possible functions as spatial definers, and to make spatial properties (which here take the form of implicit knowledge) explicit in design processes in order to increase awareness of spatial concerns in surface pattern design.Workshop experiments with design students and professional designers were used as a practical method in this work, and played a major role in the investigations. The objectives of the workshops were to explore the use of spatial concepts as design variables, and to understand the roles that they play in design processes and how they affect a design outcome. The analysis utilised a phenomenographic approach, wherein the intention was to study and describe the different types of experiences that can occur when designing surface patterns and making hidden design variables explicit, and to catalogue examples of the ways in which the participants interpreted these in their design processes. An exploratory design example was created to complement the workshop experiments. The main contribution of the research is categorised into three types of results: 1) examples in the form of students’ design outcomes, 2) knowledge gained from the workshops, and 3) feedback regarding responses to the overarching questions that framed the research presented in this thesis. Another contribution is in-depth knowledge of the field of surface patterns, and the highlighting of an area that is rarely in focus within design research. The main purpose has been to contribute to a broadening of the understanding of the design of surface patterns.