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We present ASCA temperature profiles and, when possible, crude temperaturemaps for a sample of bright clusters with 0.04<z<0.09. Together with severalpreviously published clusters, the sample includes A85, A119, A399, A401, A478,A644, A754, A780, A1650, A1651, A1795, A2029, A2065, A2142, A2256, A2319,A2597, A2657, A3112, A3266, A3376, A3391, A3395, A3558, A3571, A3667, A4059,Cygnus A, MKW3S, and Triangulum Australis. Nearly all clusters show asignificant radial temperature decline. For a typical 7 keV cluster, thetemperature decline between 1 and 6 X-ray core radii (0.15 and 0.9/h Mpc) canbe approximately quantified by a polytropic index of 1.2-1.3. Assuming such apolytropic temperature profile, the gravitating mass within 1 and within 6 coreradii is approximately 1.35 and 0.7 times the isothermal beta-model estimates,respectively.  Most interestingly, we find that temperature profiles, excluding those forthe most asymmetric clusters, appear remarkably similar when plotted againstradius in units of the estimated virial radius. We compare the compositetemperature profile to the published hydrodynamic simulations. The observedprofiles appear steeper than those in most Lagrangian simulations (Evrard etal1996; Eke etal 1997). The predictions for Omega=1 models are most discrepant,while models with low Omega are closer to our data. We note, however, that atleast one Omega=1 Lagrangian simulation (Katz & White 1993) and the recenthigh-resolution Eulerian simulation (Bryan & Norman 1997) produced clusterswith temperature profiles similar to or steeper than those observed. Ourresults thus provide a new constraint for adjusting numerical simulations and,potentially, discriminating among models of cluster formation. (ABRIDGED)Comment: Added 4 clusters, updated one; added discussion of several outliers.  Accepted for ApJ. Latex, 20 pages with figures, uses emulateapj.st

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