With a market entry game inspired by Camerer and Lovallo (1999), we study the attitudes of junior and senior employees towards strategic uncertainty and competition. Seniors exhibit higher entry rates compared to juniors, especially when the market capacity is not too low or when earnings from entry depend on relative performance. This difference persists after controlling for attitudes towards non-strategic uncertainty and for beliefs on others' competitiveness and on relative ability. Seniors are more willing to compete when they predict a higher number of competitors. This contradicts the stereotype of less competitive older employees.