After building up foreign currency denominated (FC) liabilities over several years, the balance sheets of Colombian firms might be particularly vulnerable to a shift in external conditions. We undertake four exercises in order to get a better understanding of these vulnerabilities. First, through probit/logit estimations we identify the firm-level and macroeconomic determinants of FC borrowing by non-financial corporations. Second, we investigate the implication of the balance sheet vulnerability for real activity. We find evidence of a FC balance sheet effect that transmits exchange rate fluctuations to firm-level investment, and show that this effect is asymmetric, much greater for depreciations than for appreciations. Third, using logit/probit estimations, we show that not all firms use forward exchange derivatives solely to hedge their FC liabilities. This might be a consequence of exchange rate intervention by the monetary authority, protecting against extreme exchange rate misalignments. Finally, we report results of a survey-based qualitative analysis on the hedging policies and activities of 12 large non-financial firms.