This working paper argues that the growing field of transparency, participation and accountability (TPA) needs a conceptual reboot, to address the limited traction gained so far on the path to accountability. To inform more strategic approaches and to identify the drivers of more sustainable institutional change, fresh analytical work is needed. The paper makes the case for one among several possible strategic approaches by distinguishing between 'scaling up' and 'taking scale into account', going on to examine several different ways that ‘scale’ is used in different fields. It goes on to explain and discuss the strategy of vertical integration, which involves multi-level coordination by civil society organisations of policy monitoring and advocacy, grounded in broad pro-accountability constituencies. Vertical integration is discussed from several different angles, from its roots in politcal economy to its relationship with citizen voice, its capacity for multi-directional communication, and its relationship with feedback loops.