Low-intensity laser radiation is characterized by its ability to induce athermic, nondestructive photobiological processes. Although it has been in use for more than 30 years, this phototherapy is still not an established therapeutic modality. We have summarized the main arguments being brought up against the use of this therapy and have reviewed the literature addressing both its in vitro and in vivo effects. We conclude that low-intensity laser irradiations might be of benefit in selected indications if the existing preliminary data can be confirmed by more prospective and well-controlled studies.