human capital often depend critically on parents’ behavior and less on access to supply side services where attendance or uptake can be tracked.

As a result, as well as due to a growing literature that emphasizes difficulties with and downsides from conditionality, especially in settings with limited implementation and monitoring capacity and where there may be limited availability of the resources or facilities needed to enable households to meet conditions, there has been increasing interest in designing and evaluating alternatives to formal conditionality, including the use of “accompanying measures” ranging from nutritional supplementation, family practices training, and other modalities (Cookson, 2018; Arriagada et al., 2018). However, while there is some evidence that this ‘Cash Plus’ approach leads to positive impacts, at least in the short run (Berhman and Hoddinott, 2005; Macours et al., 2012), some follow-up studies have found effects to dissipate over a period of time (Attanasio et al. 2014), demonstrating the challenge _of sustainable_ behavior change and investments in children’s human capital needed to promote long-term welfare.

The question of how best to design ECD-focused cash transfers – in terms of program parameters, delivery mechanisms, and supplemental measures to optimize impacts on children – thus remains an open one. With conditionality difficult or impossible due to the reasons outlined above, and mixed results from straightforward informational or awareness-based programming (or “accompanying measures”) alone, there is room to explore alternative techniques of encouraging the behavior change on the part of caregivers/parents that is critical for ECD-focused transfer programs to achieve their desired ends. Here, much promise attaches to the idea of leveraging insights from the emerging field of behavioral economics, which finds that human decision-making is subject to a variety of cognitive and other biases that cause behavior to diverge from the predictions of neoclassical economics, that many of these biases are activated and exacerbated by small features of decision-makers’ contexts, and that while these effects operate for all populations, they are particularly marked for those living in conditions of poverty (Datta and Mullainathan 2012; Mullainathan and Shafir 2013). Applied to cash transfers, this suggests that even small features of the context in which program beneficiaries operate may impact decisions (and thereby outcomes) by exacerbating the effect of common features of human psychology such as limited selfcontrol, limited attention, present bias, etc. in ways that could reduce the likelihood of beneficiaries taking the kinds of decisions and actions the program is set up to generate, _even when beneficiaries can afford to take these steps and are intrinsically motivated to do so._ Behavioral economics further suggests that small tweaks – often called ‘nudges’ – can improve follow-through on behaviors critical for program success (see Datta and Mullainathan 2012). In particular, it suggests that subtle aspects of program design that have traditionally been overlooked, or at least not emphasized, can be adjusted or augmented in ways (such as the leveraging of social norms, the use of framing around the expected use of the cash rather than focusing on the enforcement of compliance with conditions, etc.) that can help to amplify the effects of cash by aligning program features more closely with intended beneficiaries’ cognitive processes and bandwidth (World Bank 2015; Datta and Mullainathan 2012; Mullainathan and Shafir 2013).

Several recent studies test the impact of such ‘behavioral interventions’ or ‘nudges’ on cash transfer beneficiaries’ decisions, actions and outcomes with promising results. For example, Moroccan cash transfer beneficiaries’ resource allocation decisions are highly sensitive to how the purpose of the funds they are given is “labeled” (Benhassine et al. 2015). Similarly, a formally unconditional cash transfer accompanied by publicity around school enrollment and health checkups for beneficiaries’ children led to substantial increases in school enrollment among the poorest quintile (Oosterbeek, Ponce and Schady, 2008). Sedlmayr et al. (2018) find promising impacts from a simple intervention that asks beneficiaries to articulate spending goals before receiving the transfer. Cohen et al. (2017) find that a non-binding commitment to give birth in a high-quality clinic increases the likelihood of transfer-receiving expectant mothers actually doing so. Right-timing transfer payments improves the likelihood of follow-through on intentions to send children to school, perhaps by reducing the opportunities for temptation spending between the time of receipt and the time of anticipated spending on educational expenses (BarreiraOsorio et al. 2011). Awkii et al (2018) find that peer support sessions for caregivers enrolled in a cash transfer program in Somalia increases children's participation in education parents’ ability to provide some basic needs. However, several gaps remain in the application of behavioral economics to cash transfers thus far, and especially to its application to ECD-focused transfers. First, given that parents and caregivers are the lead architects and 3