Abstract: Aqueous concentrates containing glyphosate herbicide which on dilution give spray solutions having higher herbicidal unit activity than prior art solutions comprise:(a) solubilized glyphosate equivalent to at least 40 grams per liter of glyphosate acid;(b) a surfactant which is (i) an amine having the formula ##STR1## where R represents a straight- or branched-chain alkyl or alkenyl group having from about 8 to about 22 carbon atoms, A represents an alkylene group, for example an ethylene or propylene group, and n and n' are integers such that n+n' has a value of from about 2 to about 8, (ii) a mixture of such amines having different groups R, the average number of carbon atoms in the groups R being from about 8 to about 22, or (iii) a mixture of such amines having different values of n and n', n and n' being integers such that in the mixture the average value of n+n' is from about 2 to about 8, R having a single value or an average value as in a mixture (ii);and optionally (c) an agriculturally acceptable in