Tracking participant progress in large Randomized Control Trials (RCT) is essential to success, yet tracking procedures are seldom discussed in the research literature. This abstract describes the procedures used during recruitment and retention to track participants in the 18‐month HomeStyles RCT. Microsoft Excel was used to create recruitment‐tracking and retention‐tracking spreadsheets that organized participants by group (experimental, control), geographic location (NJ, AZ), delivery mode (online, home visitation), and language (English, Spanish). Recruitment‐spreadsheet data were used to plot recruited participants by group x location x mode x language to enable researchers to assess and target recruitment resources (e.g., staff time, recruitment flyer printing and distribution, recruitment activities) and project when recruitment goals would be reached. The retention‐tracking spreadsheet included participant stage of RCT participation (Survey 1, Instructional Guide [IG]1, IG2, IG3, IG4, Survey 2, IG5, IG6, IG7, IG8, Survey 3, IG9, Survey 4, IG10, Survey 5), and days elapsed since last communication with RCT team or website. Charting retention‐tracking spreadsheet data permitted researchers to visualize participant progress throughout the time course of the RCT; monitor the rate at which participants completed the RCT; and rapidly intervene when participants appeared to be experiencing barriers that may cause them to become inactive and drop out. The retention‐tracking spreadsheet was annotated to indicate when and how inactive participants were contacted. Staff training and twice weekly generation of recruitment and retention data summaries were essential to making timely, informed research management decisions. Recruitment and retention tracking procedures and algorithms from this RCT have the potential to improve RCT monitoring and management practices in a wide array of health promotion and nutrition communication research studies.Support or Funding InformationUSDA NIFA #2011‐68001‐30170