Recent advances in gene editing using the CRISPR/Cas system have revolutionized genome editing, opening new horizons for human cellular and gene therapy products. Genome editing technologies are rapidly being adopted in clinical trials. However, critical non-clinical safety considerations are required to address challenges in translating research to the clinic. Here, we review current ex vivo and in vivo genome editing approaches using the CRISPR/Cas system and discuss the practical use of these methods in pre-clinical studies and in the clinic. We also discuss known limitations of genome editing in humans and the mitigation of risk factors associated with it from a non-clinical safety perspective. This review aims to aid researchers in acquiring a perspective that is essential for the safe translation of genome editing to the clinic.