Editorial on the Research Topic Insights in synthetic biology 2021: Novel developments, current challenges, and future perspectives'This "Insights into Synthetic Biology 2021" Research Topic aims to illustrate the remarkable progress of synthetic biology in many different research and application areas. These include the conceptual process of building synthetic cells from scratch, sustainable solutions to our fossil dependency that can now solve greenhouse gas emissions, proposing innovative therapeutic solutions to complex diseases, or fighting infectious diseases. SB's strength also depends on advances in methods, techniques, and algorithms, which are also presented in this Research Topic. Finally, SB is positioned in the field of education as a subject that motivates entrepreneurial aspirations.The Research Topic "Insight into Synthetic Biology 2021"has been very satisfactory in providing 15 contributions, divided into 9 mini-reviews, four original papers, and two opinion papers, which together cover the current developments and challenges in Synthetic Biology (SB). Four articles were devoted to updating tools and methods for better insertion of novel functions or better control of functions in a biological system. Li et al. elegantly summarized the main pitfalls of CRISPR technology in genome editing and proposed some solutions to overcome these difficulties. Liao et al. demonstrated high antibiotic-free plasmid stability upon insertion of the hok/sok gene system into this plasmid, opening up the possibility of using it in large-scale process production. Regarding the methods required to implement and control new functions in biological systems, Abraha and Marchisio reported the implementation in yeast of a bacterial ClpXP protein degradation system and showed that SBML level 3 is perfectly suited to describe the modular function of this orthogonal synthetic gene circuit constructed in yeast. At a higher level of complexity are the systemic principles of gene regulatory networks, whose understanding in terms of architecture, organization, dynamics, and evolution is important for the optimal engineering of biological systems, as summarized in the study by Freyre-González et al. These authors coined the term "concilion," which corresponds to a group of structural genes with their local regulators