Pemetrexed is a new cytotoxic agent that is a standard of care for the second-line treatment of non-small cell lung cancer (NSCLC) and in combination with cisplatin in treatment of malignat pleural mesothelioma. It has been studied in numerous phase II and III trials in combination with different drugs or as single agent. Recently, pemetrexed has been approved in combination with cisplatin for the first-line treatment of patients with locally advanced or metastatic NSCLC other than squamous cell histology. The toxicity is acceptable and similar to that of other NSCLC regimens. The postinduction maintenance therapy with pemetrexed is being evaluated in a phase III, double-blind, placebo-controlled study.