Wildschut's research challenges the historical view of nostalgia as a negative emotion, presenting it instead as a complex, multi-faceted experience that can have positive psychological functions, such as enhancing social connectedness, fostering meaning, and strengthening self-continuity.
His research also extends into intergroup relations, including the interindividual-intergroup discontinuity effect, which explores why groups tend to be more competitive than individuals. His work on this problem was recognised with the Gordon Allport Intergroup Relations Prize.