A dual chalcogen-bonding interaction has been developed as a means of establishing conformational control in sulfur- and selenium-containing ureas. By virtue of this dual interaction, urea derivatives adopt a planar structure bearing an X⋅⋅⋅O⋅⋅⋅X arrangement (X=S, Se). The rigidity of the structure and the acidity were found to increase in the order benzothiophene