Attendees were given posters and brochures to distribute in their localities, and, when requested, were given contact information of the officials conducting the meetings for future questions.

Localities in all three experimental groups had access to this standard outreach effort. However, localities in T0 received _only_ this information, and not the activities described below.<sup>3</sup>

**_Treatment Group 1 (T1)_** had access to the same standard outreach strategies and materials as T0 localities, but it additionally received materials with simplified information and formatting of the call for proposals, as well as additional communication channels. As the qualitative diagnostic study showed the importance of reducing the ‘hassle factors’<sup>4</sup> that people faced when attempting to access and understand information, this treatment delivered new material where information was presented with less text and using examples and familiar and easy-to-understand terms. In addition, the application forms that localities in T1 had access to were simplified by using more direct and less technical language and included examples. All materials and information used in the intervention were tested in the field prior to finalizing them. These localities also had access to additional communication channels in order to better reach potential applicants, especially those less experienced and motivated or living with time scarcity or poverty: (i) two additional meetings, one informative meeting and one follow-up meeting, with local allies in each locality (local allies were 13 people with previous experience in the region and identified through local civil society organizations to support these activities); (ii) before meetings, local allies requested authorities to hang posters and audio-messages through megaphones in public spaces of the locality that explained the steps to participate in the call for proposals; and (iii) access to a helpline through phone, text messages (SMS) or WhatsApp to answer general questions throughout the application process.

**_Treatment Group 2 (T2)_** localities received the same intervention as T1 (T0 + simplification and additional communication channels), and in addition they were exposed to: (i) modified posters from T1 with messages designed to leverage insights from behavioral sciences literature,<sup>5</sup> such as mentioning aspects of their identity as women and role as mothers when arguing the importance of participating; messages and images normalizing the participation of women in activities outside their home, setting an example of accepted behavior and challenging a social norm; and posters and text messages using loss aversion framing by telling potential participants not to miss out on the opportunity to participate; (ii) up to 37 SMS/WhatsApp messages with reminders and encouragement about the call for proposals, using some of the insights mentioned above and trying to address the intention-action gap with the reminders; and (iii) a checklist to help interested individuals complete the application process and close the intention-action gap.

We can interpret the differences in outcomes between T1 versus T0 localities as the added effect of simplification and expanded communication channels (e.g. local meetings, helpline, etc.), and T2

> 3 It is important to highlight that, as detailed in the sampling section, the call for proposals and World Bank program were promoted and implemented in many localities across five Mexican states; however, because of budgetary reasons, we restricted our sample to two of the five states: Yucatán and Oaxaca. Morover, we only ran the RCT and collected data in a subset of the available localities in these states (116, of which only 36 were part of T0).

> 4 Inefficient or unnecessary steps that might delay or prevent people from performing an intended behavior.

> 5 For a summary of these behavioral insights and how they impact these behaviors, see World Bank (2018), Closing the Gender Gap in Natural Resource Management Programs in Mexico.

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