  We have carried out multicolor linear polarimetry (UBVRI) of the brightest
stars in the area of the open cluster Trumpler 27. Our data show a high level
of polarization in the stellar light with a considerable dispersion, from $P =
4%$ to $P = 9.5%$. The polarization vectors of the cluster members appear to be
aligned. Foreground polarization was estimated from the data of some non-member
objects, for which two different components were resolved: the first one
associated with a dust cloud close to the Sun producing $P_{\lambda max}=1.3%$
and $\theta=146$ degrees, and a second component, the main source of
polarization for the cluster members, originated in another dust cloud, which
polarizes the light in the direction of $\theta= 29.5$ degrees. From a detailed
analysis, we found that the two components have associated values $E_{B-V} <
0.45 $ for the first one, and $E_{B-V} > 0.75$ for the other. Due the
difference in the orientation of both polarization vectors, almost 90 degrees
(180 degrees at the Stokes representation), the first cloud ($\theta \sim 146$
degrees) depolarize the light strongly polarized by the second one ($\theta
\sim 29.5$ degrees).
