BACKGROUND: Asthma is an important focus for pediatric health research as management of asthma symptoms is a significant challenge, and morbidity and mortality among youths with asthma remain prevalent. Treatment guidelines for asthma recommend a written asthma action plan (WAAP) that summarizes individualized instructions for daily medication use. However, WAAPs are typically written at a seventh- to ninth-grade reading level, which can be a barrier to young people in understanding their treatment, having confidence in using a WAAP, and engaging with asthma education. OBJECTIVE: Utilizing a feasibility and pilot randomized controlled trial (RCT) design, the objective of the Take Action for Asthma Control study is to test a symptom-based, computer-generated pictorial asthma action plan (PAAP) in comparison with a standard WAAP and assess the feasibility and acceptability of the asthma action plan (AAP) intervention and study procedures. The study has 3 aims: (1) estimate the effect sizes of PAAPs compared with WAAPs on outcomes (eg, AAP knowledge and medication adherence), (2) evaluate feasibility and acceptability of AAP intervention and RCT procedures from the perspectives of key stakeholders, and (3) establish whether parent and youth literacy levels are associated with treatment outcomes. METHODS: This feasibility and pilot RCT is a block randomized, 2-arm, parallel-group clinical trial, lasting 6 months in duration. At baseline, participants will be randomly assigned to receive a PAAP or WAAP generated for them and reviewed with them by their asthma physician. Study procedures will take place over 4 separate time points: a baseline clinic appointment, 1-month telephone follow-up, and 3- and 6-month clinic-based follow-ups. At each time point, data will be collected related to the main outcomes: AAP knowledge, AAP satisfaction, asthma control, pulmonary function, and adherence to daily asthma medication. A sample size of up to 60 participants (aged 8-17 years) will be recruited. Feasibility and acceptability data will be collected via one-to-one qualitative interviews with providers involved in the study and a subgroup of families that participate in the study. RESULTS: Recruitment and data collection began in May 2017 and were completed in October 2018. CONCLUSIONS: This pilot and feasibility study will test the potential efficacy, feasibility, and acceptability of an AAP intervention and study procedures. The findings will inform the design and delivery of a future definitive trial to assess the efficacy of PAAPs versus WAAPs in supporting asthma self-management among children and adolescents. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/11733.