Fifty consecutive patients with soft-tissue neck injuries following rear end collisions were studied prospectively to assess their rate of recovery. Patients were seen within 5 days of the accident, after 3 months, 1 year and 2 years, and their symptoms were classified into one of four groups (A, asymptomatic; B, nuisance; C, intrusive; D, disabling). Fourteen of 15 patients (93%) who were asymptomatic after 3 months remained symptom-free after 2 years. Of 35 patients with symptoms after 3 months, 30 (86%) remained symptomatic after 2 years. After 1 year, 26 (52%) stated that they had recovered completely, but after 2 years this had fallen to 19 (38%). Nine of the 15 patients who had improved between 3 months and 1 year deteriorated to their previous status, or worse, between 1 and 2 years. In asymptomatic cases, a prognosis that is 93% accurate after 2 years can be given after 3 months, and 86% of patients who are symptomatic after 3 months will remain so after 2 years. However, the severity of their symptoms will change during this period and will be at the same degree of severity in less than 50%.