While strategic management theories have heavily engaged with the reality of matrix organizations, leadership theories that actually focus on the people working within such arrangements are missing. We argue that (a) followers perceive dual leadership effectiveness to be more than the sum of each leader's effectiveness, (b) a core detriment to perceived dual leadership effectiveness is role conflict experienced by the follower, and (c) Leader-Member Exchange (LMX) needs to be theoretically extended to the triadic level to capture the influence of dual leadership. Specifically, followers’ role conflict and leadership effectiveness perceptions are driven not only by how they perceive their LMX relationships with both leaders, but also how they perceive the relationship quality between their leaders (dual leadership exchange, DLX). As such, even though higher LMX is still better than lower LMX, having a similar exchange relationship with both leaders reduces employees’ role conflict and, by extension, heightens dual leadership effectiveness. Additionally, we reason that when employees lack a good relationship with one of the leaders, higher DLX can act as a substitute. We find support for our hypotheses by applying polynomial regression analyses to a dataset of 111 managers from a matrix organization who report to both a regional and business unit leader.