The policy of family visits to patients admitted into intensive care units (ICUs) has been liberalised in recent years. This change has been progressive in our unit from a restricted to an open visiting policy. We have carried out this study based on Ajzen and Fishbein reasoned action theory. The aim of this study is to analyse the relationship between nurses' beliefs and attitudes towards the effect of an open visiting policy on patients, family and nurses. A descriptive correlational design was used. The sample included 46 intensive care nurses from a teaching hospital in Spain, who completed two self-administered anonymous questionnaires. One of them, derived from empirical results of Kirchhoff et al. (1993) and Simpson et al. (1996) studies, was a Likert-type scale including 26 items divided in three subscales (patient, family and nurses). This scale was used to obtain the nurses' beliefs regarding the effects of open visiting. The second questionnaire was a differential semantic scale (used by the previous authors), which analysed nurses' attitudes towards visiting on the patient, family and nurses. Nurses' beliefs about the effect of visiting were positive, achieving a mean value of 3.001 (patient 3.04, family 3.23 and nurses 2.78) on a scale with a maximum value of 4. The mean score obtained on the scale of attitudes toward an open visiting policy was 6.005 (patient 6.41, family 6.37 and nurses 5.22), with a maximum of 7. The correlation between beliefs and attitudes was significant and positive (r = 0523, p < 0.0001). Comparison of sociodemographic variables with beliefs and attitudes disclosed no statistically significant differences, except for the two following variables: attitude and having children (t = -2.254, p = 0.03) which obtained a higher score. There is a correlation between nurses' beliefs and attitudes regarding the positive effects of open visiting on patients, family and nurses.