The invention relates to a concentrate for cleaning and disinfection which comprises (i) one or more alkyl alcohol alkoxylates, (ii) one or more formaldehyde donor compounds, (iii) optionally one or more biocidal, in particular fungicidal, active ingredient(s), (iv) optionally one or more glycols and (v) optionally up to 10% by weight of water. Concentrates according to the invention can be formulated with a high content of formaldehyde donor compound without an undesired formaldehyde odour arising.
