This study investigates what leads managers to allocate constrained cognitive effort toward new versus familiar aspects of a business. Specifically, we explore advice giving by venture capital firms (VCs) to their portfolio companies, distinguishing between business topics on which a VC has advised other ventures in the past and topics new to the VC that may be outside its areas of expertise. We use both demand-side (venture-driven) and supply-side (VC-driven) perspectives to offer a novel theory about the antecedents of cognitive effort underlying advice giving. Empirical tests in a unique data set of French VCs show that both perspectives explain important aspects of advice-giving dynamics for VCs. VCs facing dynamic environments and capacity constraints strongly respond to stimuli from ventures, but VCs also adjust their behavior as they accumulate experience in ways that reflect both expanding confidence in their ability to add value and concerns about overextension of their efforts, depending on the valence of VC experience. Our findings provide important insights to the antecedents of cognitive effort and to research on the VC–venture relationship by exploring the dynamics of how advice-giving relationships evolve over time as VCs gain experience.