This study aims to test the relationship between financial constraints and investment for Brazilian firms using the strategy outlined by Almeida and Campello (2007), which is robust to several criticisms raised in the literature. The main results suggest that: 1) firms classified as unconstrained, in general, behave exactly like predicted by the neoclassic model; and 2) firms classified as constrained behave in a way that is consistent with Almeida and Campello (2007) model. These results differ substantially from those reported in previous studies in Brazil and constitute a novel evidence of a credit multiplier effect at the firm level.