Most of the literature devoted to the study of deverbal nominalizations concentrates on the complex event reading (e.g. La concentración de partículas tiene lugar a temperatura ambiente ‘The concentration of particles takes place at room temperature’) and the object reading (e.g. El paciente tenía concentraciones de calcio en el hombro ‘The patient had calcium concentrations in the shoulder’), while nominalizations denoting states (e.g. La concentración de Sherlock Holmes duró cinco horas ‘Sherlock Holmes’ concentration lasted five hours') have remained, in general, understudied. In this paper we present their empirical properties and argue that, despite the empirical differences, state nominalizations and event nominalizations can receive a unified account. We show that in Spanish, Catalan, French, English and German the question of whether a deverbal nominalization denotes a state or an event, or is ambiguous between both readings depends on independent properties of the verbal base, allowing us to propose a unified account of both classes of nominalizations: the productive nominalizers in these languages can only denote the aspectual notions contained in the base's Aktionsart. We further argue that other languages, like Slovenian, have productive nominalizers that can operate over the external aspect of the predicate; in these cases, the nominalization can denote aspectual notions not contained in the base's Aktionsart.