{Reference Type}: Journal Article {Title}: Employing Photocatalysis for the Design and Preparation of DNA-Encoded Libraries: A Case Study. {Author}: Kölmel DK;Zhu H;Flanagan ME;Sakata SK;Harris AR;Wan J;Morgan BA; {Journal}: Chem Rec {Volume}: 21 {Issue}: 4 {Year}: Apr 2021 {Factor}: 6.935 {DOI}: 10.1002/tcr.202000148 {Abstract}: This Personal Account describes the authors' foray into DNA-encoded libraries. The article addresses several key aspects of this hit generation technology, from the development of new synthetic methodology to the subsequent conception, design, and delivery of a DNA-encoded library. In particular, we have been engaged in adapting photocatalytic reactions to the idiosyncratic requirements of DNA-encoded chemistry. We have chosen one such methodology, namely a photocatalytic [2+2] cycloaddition reaction, to showcase how we employed property-based computational analyses to guide the selection and validation of building blocks for the production of a library. Ultimately, these novel bond disconnections and design principles led to the assembly of a DNA-encoded library that is composed of structurally diverse compounds within largely desirable property space and, therefore, well positioned to deliver novel chemical matter for drug discovery programs.