The present invention relates to methods and compositions for rendering a surface resistant to bio-film formation by a combination of an alkanediol and an antimicrobial agent (and, optionally, an organic hydroxy acid). The invention provides for compositions which may be used to render surfaces bio-film resistant, articles having bio-film resistant surfaces, and methods for their preparation. The present invention may be advantageously applied to medical articles as well as articles used in non-medical contexts, such as child care or food preparation.