INTRODUCTION:Although evidence-based, the 5A's (Ask, Advise, Assess, Assist, and Arrange) for smoking cessation are often incompletely delivered by primary care providers. This study examines whether a computer tablet 5A's intervention improves primary care provider adherence to the 5A's. STUDY DESIGN:Cluster RCT. SETTING/PARTICIPANTS:All primary care providers in three urban, adult primary care clinics were randomized for participation. Any English- or Spanish-speaking patient with a primary care appointment who had smoked >100 lifetime cigarettes and at least one cigarette in the past week was eligible. INTERVENTION:A cluster RCT comparing computer-facilitated 5A's with usual care assessed effects on provider adherence to each of the 5A's as determined by patient report. Intervention subjects used a computer tablet to complete the 5A's immediately before a primary care appointment. A tailored, patient handout and a structured, clinician guide were generated. Data were collected in 2014-2015 and analyzed in 2016-2017. MAIN OUTCOME MEASURES:Provider adherence to the 5A's. RESULTS:Providers (N=221) saw 961 patients (n=412 intervention, n=549 control) for a total of n=1,340 encounters with n=1,011 completed post-visit interviews (75.4% completion). Intervention providers had significantly higher odds of completing Assess (AOR=1.32, 95% CI=1.02, 1.73) and Assist (AOR=1.45, 95% CI=1.08, 1.94). When looking at first study visits only, intervention providers had higher odds for Arrange (AOR=1.72, 95% CI=1.23, 2.40) and all 5A's (AOR=2.04, 95% CI=1.35, 3.07) but study visit did not influence receipt of the other 5A's. CONCLUSIONS:A computer-facilitated 5A's delivery model was effective in improving the fidelity of provider-delivered 5A's to diverse primary care patients. This relatively low-cost, time-saving intervention has great potential for smoking cessation and other health behaviors. Future studies should identify ways to promote and sustain technology implementation. TRIAL REGISTRATION:This study is registered at www.clinicaltrials.gov NCT02046408.