peer reviewedThe multiwavelength study of massive stars has revealed many phenomena that are intimately related to their multiplicity. Colliding winds in massive binaries play indeed a significant role in thermal X-ray emission, particle acceleration, or even dust formation in such systems. In this context, the identification of binaries and the determination of their orbital parameters is a pivotal issue. We first briefly describe the CARLINA project. The sensitivity and imaging capability of Carlina are perfectly adapted for the study of binary systems. Considering its expected specifications, Carlina will operate in complementarity with ELTs and kilometer baseline interferometers. Then, we discuss some prospects for the multiplicity investigation of massive stars, on the basis of the expected performances of the prototype currently studied at the Observatoire de Haute-Provence (OHP)