We propose a distinction between two types of interpersonal compatibility in determining partner preferences for joint tasks: outcome compatibility and strategic compatibility. We argue that these two types of compatibility correspond to preferences for similar and complementary task partners, respectively. Five studies support this distinction. A pilot study demonstrates that established scales for measuring attitudes and values (variables associated with similarity effects) capture more information about desired outcomes, whereas established scales for measuring dominance (the variable most widely associated with complementarity effects) capture more information about desired strategies. Studies 1a and 1b demonstrate that framing the same variable as either an outcome variable or a strategic variable can predict partner preference (i.e., similar or complementary). Finally, Studies 2a and 2b address why complementarity may offer a strategic advantage over similarity in task pursuit: complementarity allows two individuals with contrasting strategic preferences to “divide and conquer” tasks that require multiple strategies.