The aesthetic appreciation of a product is often described without taking into account that the product has been designed for a purpose; for instance, merely based on the product’s appearance. This dissertation examines the kind of aesthetic appreciation that involves recognizing that the product has been designed (as a means) to achieve a particular effect and, more specifically, evaluating how the product achieves such effect. It focuses on the principle of efficiency or “MEMM”, which indicates that people perceive beauty in a product when they perceive it to achieve “the maximum effect” with “the minimum means”. A combination of research methods is used to address the following four questions: (Q1) Is the appreciation of a product affected by knowledge of the product’s intended effect and, if so, how? (Q2) How can the aesthetic appreciation of a product be understood based on the principle of MEMM? (Q3) Is the aesthetic appreciation of a product positively affected by the perception of the product as the minimum means achieving the maximum effect? (Q4) How can designers enhance a product’s aesthetic appeal by considering the product as the means to achieve an intended effect? A mixed-methods investigation of Q1 indicates that intention knowledge does affect product appreciation, partly insofar as it enables an (aesthetic) evaluation of the product as a means to achieve an intended effect. A conceptual analysis of Q2 reveals how a product and its intended effect can be judged to be the minimum means and the maximum effect with grounds in a set of assumed alternatives for both the means and the effect. An experimental examination of Q3 provides evidence that a product is aesthetically appreciated when it is perceived to achieve more than other products from the same category (the maximum effect) by making an efficient use of resources (the minimum means). A mixed-methods study of Q4 finally suggests a set of qualities that designers can aim at when defining an intended effect and developing a product (means), and also indicates the aspects of the product that can be manipulated based on these qualities. The findings here presented have a number of implications. For design research, they indicate that people’s (aesthetic or non-aesthetic) experience of a product or service should be examined with attention to their knowledge of the designer’s intended effect. For design practice, they propose a strategy for enhancing aesthetic appeal that involves manipulating aspects such as user interaction and that can, therefore, not just help develop a beautiful product, but a beautiful service too. For design education, they suggest the value of teaching that beauty and efficiency can be combined in designing and experiencing a product or service; they also trigger a reflection on means- and effect-based teaching approaches. For marketing, they identify several qualities that potential consumers might appreciate in a product or service, qualities that can thus guide the creation of an advertisement and that can make the advertisement, in itself, more appealing. With regards to the day-to-day experience of products and services, they offer an understanding of the reason why people might like a particular product or service, which in turn might help them make more knowledgeable consumer choices. Because MEMM can be applied to many other artifacts besides products and services, the findings here presented are also relevant to fields of knowledge and practice such as the arts.@en