OBJECTIVE Treatment of rheumatoid arthritis (RA) should aim at full remission. The aims of this study were to define: (1) how many patients reached ultrasound power Doppler (US-PD) remission in a cohort of patients with early RA (ERA) compared with longstanding RA (LSRA); (2) possible predictors of US-PD remission; and (3) how many patients with and without US-PD remission relapsed after 1 year of follow-up in ERA and LSRA. METHODS 48 patients with ERA and 46 with LSRA with disease activity score <1.6 underwent US assessment. Six hand and wrist joints were studied for active synovitis. 56.2% of patients with ERA and 50.0% of those with LSRA fulfilled American College of Rheumatology (ACR) remission criteria. RESULTS 43.7% of patients with ERA and 17.4% of those with LSRA had no evidence of synovitis at US evaluation. Using a stricter clinical definition of remission (ie, ACR criteria), US evaluation confirmed clinical remission in 66.7% of patients with ERA and 26.1% of those with LSRA. Early disease was predictive of clinical US remission. 20.0% of patients with RA who had a negative PD signal at the US evaluation had a flare during the 12-month follow-up period compared with 47.1% of patients who had a positive PD signal. CONCLUSIONS US-PD remission occurs in half of patients with ERA and in a minority of patients with LSRA in clinical remission. Early disease seems to be the major determinant of full remission.