  The pattern speed in one of the fundamental parameters that determines the
structure of barred galaxies. This quantity is usually derived from indirect
methods or by employing model assumptions. The number of bar pattern speeds
derived using the model independent Tremaine and Weinberg technique is still
very limited. We present the results of model independent measurements of the
bar pattern speed in four galaxies ranging in Hubble type from SB0 to SBbc.
Three of the four galaxies in our sample are consistent with bars being fast
rotators. The lack of slow bars is consistent with previous observations and
suggests that barred galaxies do not have centrally concentrated dark matter
halos. This contradicts simulations of cosmological structure formation and
observations of the central mass concentration in nonbarred galaxies.
