 In addition to approaching cells as objects of scientific study, contemporary researchers often adopt an engineering approach to cells. One context is in the domain of synthetic biology in which researchers engineer cells, sometimes for research ends but other times to generate products society finds useful (see the entry on  philosophy of systems and synthetic biology).  The recent development of gene editing tools such as CRISPR opens up both epistemic and ethical issues (for the ethical issues, see the entry on  neuroethics).  One context in which attempts to synthesize cells has played a central role is in the attempt to understand the origins of life. Much of the research on origins of life involves the development of protocells—self-organized, spherical systems composed of lipids (Rasmussen et al. 2009). This has become a prominent topic of inquiry for both theoretically minded biologists and philosophers of biology (see the entry on  life;  Bedau 2012; Moreno 2016; Dunér, Malaterre, and Geppert 2016).