In recent years, design approaches to policymaking have gained popularity amongst policymakers. However, a critical reflection on their added value and on how contemporary 'design-thinking' approaches relates to the classical idea of public administration as a design science, is still lacking. This introductory paper reflects upon the use of design approaches in public administration. We delve into the more traditional ideas of design as launched by Simon and policy design, but also into the present-day design wave, stemming from traditional design sciences. Based upon this we distinguish between three ideal-type approaches of design currently characterizing the discipline: design as optimization, design as exploration and design as co-creation. More rigorous empirical analyses of applications of these approaches is necessary to further develop public administration as a design science. We reflect upon the question how a more designerly way of thinking can help to improve public administration and public policy.