Among A-type stars only a small group, known as lambda Boo, are
 affected by metal deficiencies. These deficiencies are the result
 of an interaction between the star and its environment
 (Waters et al., 1992 A.A. 262, L37).
 The analysis of optical and UV spectra have proven that lambda Boo
 are Pop I stars with atmospheric abundance patterns similar to
 those of the ISM (Venn and Lambert, 1990 Ap.J. 363, 234). An IR
 excess has been detected by IRAS for 3 out of 25 known lambda Boo
 and has been associated with thermal emission of a dusty envelope.
 These observations together with complementary information on the
 position in the HR diagram (of lambda Boo with known parallaxes)
 lead us (Gerbaldi et al. 1993 ASP Conf. 44, 413) to interpret the
 characteristics of lambda Boo as a sign of the very young age of
 these stars which are just arriving on the ZAMS. Waters et al.
 (1992) suggested that the observed abundance anomalies are the
 result of the separation of gas and dust in a disc surrounding the
 star during the last phases of accretion and this disc being the
 remnant of the material from which the star was formed. According
 to this scenario, young A-type stars should present an IR excess
 which could have been detected only partly by IRAS due to its
 limited sensitivity.
 The main goal of this proposal is to point out the IR properties
 of the stellar environment for stars in the spectral range B9-A3
 (wherein we find the lambda Boo known up to now). We want to
 observe a sample of stars which belong to young open clusters or
 associations, since the lambda Boo, being field stars, are not
 suitable to establish a relation between the presence of an IR
 excess and the stellar age. That is why we selected clusters
 of various ages less than 8 to 10E7 years in order to assure
 the time scale related to the stellar environment.