Homoeoprophylaxis (HP) is the use of homoeopathically prepared substances to prevent targeted infectious diseases in recipients. Its first use in an epidemic of Scarlet Fever was documented in 1801. It has been used throughout the world since then for both short-term and long-term preventative purposes. The effectiveness and safety of Golden's long-term HP program using homoeopathically prepared substances to prevent targeted infectious diseases in recipients was tested through two research projects. The effectiveness of the program could not be established with statistical certainty given the limited sample size and the low probability of acquiring an infectious disease. However, a possible level of effectiveness of 90.3% was identified subject to specified limitations. Further research to confirm the effectiveness of the program is justified. Statistically significant results were obtained that confirmed the safety of the program both in absolute terms as well as compared to all other methods of disease prevention studied. It also appeared possible that a national immunisation system where both vaccination and HP were available to parents would increase the national coverage against targeted infectious diseases, and reduce the incidence of some chronic health conditions, especially asthma.