Introduction - A major outbreak began in Réunion in April 2005 and affected more than 35% of the island’s population. On April 19, 2007, the Ministry of Health announced that Réunion was now in an inter-epidemic phase of chikungunya. Method - During the inter-epidemic phase, chikungunya surveillance relies on a biological surveillance system based on laboratory reporting of borderline or positive IgM results, positive RT-PCR tests, or chikungunya virus isolations. Results - Between April 19, 2007, and April 18, 2008, a total of only 6 cases met the definition of probable cases. No confirmation of recent infection (no positive RT-PCR results out of 1,656 tests performed) or any temporal-spatial clustering of cases was detected in Réunion during this inter-epidemic year. Discussion - The absence of biologically confirmed cases, the very low proportion of probable cases (4.9% of cases investigated), and the absence of secondary cases among contacts of reported cases do not support the continued circulation of the chikungunya virus on the island of Réunion; however, sporadic transmission at a low level cannot be ruled out at this time. Thus, the biological surveillance of chikungunya implemented in Réunion since April 19, 2007, appears to be the most appropriate epidemiological surveillance method for an inter-epidemic situation, as it identifies clusters of cases as early as possible to prevent a potential resurgence of the epidemic. (R.A)