This study concerns the changing and variable agreement patterns with twenty-one low-frequency collective nouns (e.g. trio) in British English. The data come from the 1990 and 2000 CD-ROM editions of The Independent. The token frequencies of nouns do not appear to affect the preference for singular verb agreement. There are, however, clear differences between noun types, as is typical for lexical diffusion. Most nouns have developed a strong preference for singular verb agreement, some remain variable, and some prefer the plural. Many of the agreement patterns for individual nouns can be motivated with reference to the characteristics of the nouns rather than to the semantics of the verbs. This investigation found no evidence that singular verb agreement, which is argued in this study to be the unmarked alternative, is generally on the increase. Rather it seems that nouns which prefer plural verbs continue to move towards plural agreement.