Synthetic biology is a new scientific field that gained prominence from the early 2000s. It has been defined as the engineering of biology and the promises that it holds are enormous. The aim of this thesis is to understand the practices of synthetic biologists philosophically: what are synthetic biologists actually aiming for and how does it differ from other and earlier approaches to biology? The main focus is on the idea that synthetic biology aims to construct, synthetize and design biological systems. What do these terms entail and how do they differ from other scientific practices? This thesis explores these questions through four chapters. The first chapter deals with the different conceptions of constructivism in philosophy of science, namely the idea that science does not describe, but constructs its object. It offers a classification of the different programs that have been developed under this banner, as well as an origin story of these constructivist claims. One form of constructivism, which I call constructive realism, is defended and elaborated, mainly through an examination of the work of Bruno Latour. It is a form of constructivism that concerns not so much the construction of cognitive beliefs, but one concerned with material interventions and transformations of the world. Constructive realism is perhaps better dissociated from forms of social constructionism, and linked to claims found in French epistemologists, such as Gaston Bachelard, or in philosophers of experiment, such as Ian Hacking. If constructive realism is indeed a tenable position, how should we then face the challenge of synthetic biology? In order to meet this challenge, the second chapter introduces the conceptual distinction between regimes of articulation and regimes of purification. Construction must be understood not only as a practice of constructing beliefs or theories that answer specific questions (what I call purification), but also as constructing novel phenomena and data domains that shape new questions to be asked (what I call articulation). Moreover, such a conceptual distinction offers us a new normative framework, inspired by Vinciane Despret: science can be criticized, not only for giving poor answers, but also for asking poor questions. These conceptual tools are subsequently mobilized to argue that the specificity of synthetic biology resides in a novel regime of articulation: it differs from earlier episodes in biology by articulating new data domains and therefore enabling radically new questions to be asked. The third chapter explores this shift through the history of the life sciences, more particularly the history of molecular biology. Following Evelyn Fox Keller, a strong scepticism towards formal and mathematical proofs in early experimental and molecular biology must be acknowledged. This was a result of seeing nature as a trickster, an unpredictable 'raven' that always produced new surprises. The specific mechanisms of biological cells were a product of contingent evolutionary histories that escape prediction by formal approaches. The chapter argues that this has shifted in recent decades, mainly due to the development of genomics and the Human Genome Project. Within these new developments, formal approaches became feasible and attractive, mainly due to the different nature of data to be considered. Through an examination of the cases of systems biology, Artificial Life and synthetic biology, I argue that within these novel disciplines a different attitude towards contingency and complexity is maintained: one that neither ignores nor celebrates, but rather acknowledges complexity precisely in order to surpass it. This is what I call the postcomplex regime of articulation. By taking the case of the transformation of the question on the origins of life as exemplary, the claim is defended that these postcomplex life sciences are interested in articulating a universal biology rather than the particular, contingent 'terrestrial' biology. Life can only be understood by going beyond the particular and the messy towards the universal and the necessary. Here biology and engineering finally meet. For in this shift towards more formal and abstract approaches, an engineering angle becomes visible and feasible. To understand this process, chapter four sketches the parallel and the all-too-often-forgotten history of engineering. For engineering has a history of its own; it was not just waiting outside of history to enter the scene. Too often engineering and its history have been ignored at the cost of a focus on theory and science. This final chapter, therefore, develops two claims. First of all, engineering is understood as a specific attitude, namely one where it is not nature who is the trickster, but rather the engineers: they possess what one could call mētis, or a cunning spirit. The aim of the engineer, exemplified by Odysseus and his Trojan Horse, is that of tricking the opponent into doing things that he was not 'intended' to do. In the case of synthetic biology, this opponent is biological nature. Secondly, more recent shifts in 20th century engineering are examined, which center around the question of how to situate this mētis in a range of practices that aspire to be scientific. Since the 1970s, I argue, the notion of design has offered a promising way out: design science, although contested in content, could offer a mold in which this mētis could be shaped as a respectable scientific approach. A number of recent graduates, trained according to these new engineering curricula, became the key players in synthetic biology. As a Trojan Horse, mētis was smuggled into biology by means of the augmented status of design science. Nature as a raven-trickster, however, was mostly thrown out in this process. In the epilogue, finally, I highlight some alternative voices in biology, both in ethology and in fields more akin to synthetic biology, such as biomimicry and metagenomics. Moreover, I spell out some further consequences of the views that I develop in this thesis, mainly concerning the broader concept of technoscience and the political dimension of articulation and purification.