The tuberculosis surveillance system in the Balearic Islands was assessed from 2005 to 2007. Applying the capture-recapture method the completeness of this system was evaluated to be 58.4%. When a new electronic recorded data was included in Primary Health Care, up to 66.5% was obtained. This new source of data increased the detected cases of pulmonary tuberculosis from 572 to 681. As a result, the estimated annual incidence rate increases from 18.9 cases/10(5) to 22.6 cases/10(5) [95% CI, 20.9-24.3], similar to figures issued by WHO.