As skills of labor-market entrants are usually not directly observed by employers, individuals acquire skill signals. To study which signals are valued by employers, we simultaneously and independently randomize a broad range of skill signals on pairs of resumes of fictitious applicants among which we ask a large representative sample of German human-resource managers to choose. We find that signals in all three studied domains - cognitive skills, social skills, and maturity - have a significant effect on being invited for a job interview. Consistent with the relevance, expectedness, and credibility of different signals, the specific signal that is effective in each domain differs between apprenticeship applicants and college graduates. Whi...