Happy people seem to have it all--relatively stronger interpersonal relationships, higher incomes, better physical health, and even longer lives. But before dismissing happy people's success as plain good luck, researchers should investigate the mechanisms by which happiness might engender positive outcomes across multiple life domains. The current dissertation proposes that inducing positive emotions--the hallmark of happiness--at the beginning of a self-improvement endeavor can act as a trigger for promoting greater self-reported effort and persistence. Across two studies, I found that engaging in a positive writing task (i.e., a trigger) before beginning a self-improvement (i.e., kindness) intervention increased effort during the intervention, which then predicted greater well-being. Specifically, Study 1 examined the effect of writing about gratitude, optimism, or an intensely positive experience (versus a neutral topic) at the beginning of a 3-week kindness intervention on effort. I found that the positive writing tasks predicted greater effort toward performing kind acts, which in turn predicted greater well-being immediately following the intervention and at a 2-week follow-up. No significant differences emerged among the triggers. In Study 2, I explored the effects of the gratitude writing task in more detail, extended the intervention period to 6 weeks, and varied the deployment of the trigger to determine whether more frequent (i.e., weekly) engagement in the positive writing task predicted greater effort and persistence throughout. After writing a gratitude letter (versus writing about their week), individuals reported relatively greater elevation, which predicted greater effort throughout the intervention; in turn, replicating Study 1, greater effort predicted greater well-being immediately following the intervention. Importantly, writing a gratitude letter at baseline did not influence well-being as far as the 1-month follow-up time point. However, the group that wrote weekly gratitude letters (versus all other conditions) showed the highest levels of elevation and effort throughout the intervention, which predicted well-being following the intervention and 1 month later. Thus, engaging in a trigger before a self-improvement program can promote effort and persistence on the program, and performing weekly triggers might be especially motivating.