Analysis of the literature about functions of health volunteers in ALS.Analysis of the literature about functions of health volunteers in ALS.Article selection in MEDLINE, CINHAL and EMBASE.Analysis of the literature about functions of health volunteers in ALS.Article selection in MEDLINE, CINHAL and EMBASE.The notion of health volunteer has several meanings, and relates to different models varying between substitution and supply. The role of volunteers in a French and two Canadian NPO are described.Analysis of the literature about functions of health volunteers in ALS.Article selection in MEDLINE, CINHAL and EMBASE.The notion of health volunteer has several meanings, and relates to different models varying between substitution and supply. The role of volunteers in a French and two Canadian NPO are described.The function of the volunteer integrates potentially interpersonal aid relationships, social mediation, and active functional help components.