In the current Perspective article, we critically review and discuss the importance of solvent effects on multicomponent reactions, likely the most neglected aspect in this research field. Although solvent-free reactions may be desirable sometimes, most multicomponent reactions still require a solvent to properly promote them. This requirement makes the knowledge of all drawbacks and advantages of each solvent a central issue when trying to optimize multicomponent reactions. Yet, only a few studies with actual evidence of solvent effects on these key reactions have been published. For the quantitative effects of solvents, studies are even scarcer. In this Perspective, we argue that greater efforts should be directed to such fundamental studies.