<p>Interactions between nucleic acids and proteins are essential requirements for the viability of cellular life because they are indispensable for many basic biological processes. DNA is typically presented as a specific double-stranded helical structure but nucleic acids have great structural flexibility. Current knowledge demonstrates that the structural conformations of nucleic acids play critical roles in protein-DNA interactions. This book presents a collection of research findings published in the Special Issue of the <em>International Journal of Molecular Sciences</em> titled Impacts of Molecular Structure on Nucleic Acid-Protein Interactions.</p><p><br></p><p>The breadth of research findings reported here demonstrates that the structural flexibility of nucleic acids plays critical roles in their interactions with proteins with important implications across a range of human diseases including cancer and some infectious diseases.</p><p><br></p><p>Prof. Richard Bowater</p><p>University of East Anglia Norwich United Kingdom</p><p><br></p><p>Prof. Václav Brázda</p><p>Institute of Biophysics of the Czech Academy of Sciences Brno Czech Republic</p>