When faced with a dealer's 9, hitting on a soft 18 (an Ace and a 7) is generally considered a strategic choice in blackjack. The dealer's strong card means they have a good chance of reaching a high total, so improving your hand could be beneficial. While you have a decent total, hitting presents an opportunity to either strengthen your hand or create more chances for winning. Therefore, hitting soft 18 against a dealer's 9 is typically advisable.