In order to assess the effectiveness of sildenafil under routine conditions of use in primary care settings and to evaluate its impact on patient's life satisfaction and partner's satisfaction with treatment for erectile dysfunction (ED), an open, multicentre, observational, prospective study was designed in which 2816 patients were treated with sildenafil for at least 10 weeks. Effectiveness was assessed using the International Index of Erectile Dysfunction (IIEF), life satisfaction was measured with 'Life-satisfaction Check List' (LISAT 8), and EDITS was optionally used to assess the partner's satisfaction with ED therapy. Sildenafil was effective in 86.6% of patients. All dimensions of IIEF significantly increased with sildenafil, particularly erectile domain which overall sample mean score improved was 13.2 points (P < 0.001). The greatest increases in satisfaction with all aspects of life were seen in sex life and relationship with partner dimensions. The patients' partners, answered by a minority of partners, were highly satisfied with the treatment and its rapid action, therefore they were in favour of continuing with same. The adverse events occurring were similar to those seen in clinical research on sildenafil in the premarketing phase. No control group was included in this study.