Probiotics is a field of science, medicine and business that is growing rapidly. Regulatory agencies, especially in North America, are slow to understand these concepts and embrace and enforce United Nations and World Health Organization Guidelines. In order to advance the science and efficacy of probiotics, industry needs to self-regulate and ensure that high standards of products are met, then trials must be performed on human subjects using appropriate sample size, design and target population. With the support of granting agencies, such studies will provide valuable information on the efficacy and limitations of probiotics, and the mechanisms by which they confer their activity. In addition, regulatory authorities need to establish and enforce a ‘standard of identity’ and only allow products to be called probiotic if sufficient documentation is generated.