To evaluate activity and toxicity of a non platinum-based triplet including Gemcitabine, Ifosfamide and Navelbine (GIN) in advanced NSCLC. Stage IIIB/IV NSCLC patients with WHO PS < 2 and bidimensionally measurable disease entered the study. Gemcitabine 1000 mg/sqm day 1 and 1000-800 mg/sqm day 4, Ifosfamide 3 g/sqm day 1 (with Mesna), Navelbine 25 mg/sqm day 1 and 25-20 mg/sqm day 4 were administered intravenously every 3 weeks. Objective responses (ORs) were evaluated every 2 courses: a maximum of 6 courses were administered in responding patients. According to Simon's optimal two-stage design more than 18 ORs out of 54 patients were required to establish the activity of this regimen. Fifty patients entered the study. Main characteristics of the 48 evaluated patients were: median age 63 years, ECOG performance status 0 = 65%, stage IV disease 79% and non-squamous histology 71%. The total number of courses administered was 200, median per patient 4 (range 1-6). Toxicities were evaluated according to WHO criteria: neutropenia grade 3-4 occurred in 47% of the courses; thrombocytopenia grade 3-4 in 6.6%; anaemia grade 3 in 3.5%. Twelve episodes of febrile neutropenia were reported and three patients required hospital admission. No toxic death was reported. Non-haematological toxicity, including skin rash, alopecia and fatigue, were generally. Twenty-five ORs (1 complete response and 24 partial responses) were obtained for a response rate of 52% (95% CI: 37.4-66.5%). One-year survival was 46.5%. This non-platinum-based outpatient triplet showed promising activity against NSCLC with myelosuppression, in particular neutropenia, being dose-limiting. The GIN regimen may represent a valuable alternative to standard platinum-based doublets and triplets in the treatment of advanced NSCLC and further studies with this platinum-free combination are warranted.