The distribution of crosslinks between the polymer phases infilled and unfilled blends of natural rubber (NR) and high cis-polybutadiene rubber (BR) was studied using a swollen-state NMR technique which correlates spectrum line widths to crosslink density In the lilied blend systems this distribution is expressed in terms oi the curative loading required to give the same line width in a single polymer vulcanizate; a small bias in favour of the BR is found. For the gum blends the distribution can, additionally be expressed in actual crosslink densities, where a similar small bias is observed.