Nowadays, a modern walk-in closet is an indispensable part of almost every residence, because it helps solve many problems associated with lack of space. Custom-built, it enables optimum use of storage space, which is adapted to individual needs and wishes. For the purposes of my diploma thesis, an overview of the Slovenian built-in furniture industry was prepared. With the survey, Slovenian buyers were asked what they think about walk-in closets; further, the most important purchase factors for the walk-in closet were defined, and the opinion of respondents on integrating smart functions in modern household furniture was analysed. Using the AHP method, it was detemined which walk-in closet features drive the customer purchasing decision. With the SolidWorks program we designed a modular walk-in closet system. We constructed a walk-in closet that enables optimum use of storage space and is ergonomically adapted to individual needs and enables integration of contemporary information and communication technology or smart function.