The role of precautionary radiotherapy of the neck in laryngeal cancers (except T1-T2 glottic and some T1 supraglottic cancers) N0 at the clinical staging was investigated. Two-hundred and fifty-three patients were examined: 143 were irradiated only on T, and 110 also on the neck. Radiotherapy of the neck in the latter group was performed either by means of two large opposed fields of photon beams including T and N, or by means of fields of photon beams on T and electron beams (8 x 12 cm2 average) on the neck, to quite exclude any risks for the spinal cord. The dose was 45-50 Gy (2 Gy/fraction/day; 5 fraction/week) in 4-5 weeks. A comparison of the results obtained in the two groups, in terms of survival-rate and relapse-free time, indicates that radiotherapy reduces the change of relapses on N (6.1% vs. 14.62% at 3 years; p = 0.04) and improves the patient's survival chances (82.5% vs. 68.4% at 3 years; and 80.8% vs 63.4% at 5 years). Our data were then compared with literature data on the importance of N field size in radiation treatment. As a rule, some authors enlarge the field to be treated to a total nodal neck irradiation, but their results are not significantly different from those we obtained with 8 x 12 cm2 field size.