<p>Russian Dative-Infinitive-Structures (DIS) have been a matter of debate, with focus on such issues as mono vs. bi-clausality, modal flavour, TAM features and case-marking. I argue that all contextual realizations of Russian DIS sentences express a single flavour in root indicative clauses — alethic modality and exhibit the constraint on perfect infinitives in non-negative clauses. The Perfective Infinitive Constraint is canceled in other varieties of DIS sentences which do not express alethic meanings and are realized in irrealis or usual contexts. These asymmetries are explained by the fact that root DIS declaratives unlike irrealis DIS clauses have deictic tense. On formal accounts, deictic tense comes from the TP layer above the infinitive phrase, and the illocutionary force and modal flavour come from the upper CP layer above the TP. Root DIS declaratives enter the derivation as bi-clausal but undergo restructuring as the border between TP and VP is removed. The dative subjects of DIS sentences are raised out of the embedded infinitival clause and lack the animacy condition. The syntax and semantics of DIS sentences are valued across an overtly similar sentence pattern with embedded infinitives ― Dative-Predicative-Structures (DPS). I argue that Russian DPS sentences are control structures that implement a different mechanism of case assignment. Russian infinitival clauses by default retain deictic tense: this factor overrides the control versus raising distinction, but some types of both control and restructuring predicates block deictic tense for semantic reasons.</p>