Probably enzymes are not dispersed in the cytoplasm, but are bound to each other and to specific cytoskeleton proteins. Associations result in substrate channeling from one enzyme to another. Multienzymatic complexes, or metabolons have been detected in glycolysis, the Krebs cycle and oxidative phosphorylation. Also, some glycolytic enzymes interact with mitochondria. Metabolons may associate with actin or tubulin, gaining stability. Metabolons resist inhibition mediated by the accumulation of compatible solutes observed during the stress response. Compatible solutes protect membranes and proteins against stress. However, when stress is over, compatible solutes inhibit growth, probably due to the high viscosity they promote. Viscosity inhibits protein movements. Enzymes that undergo large conformational changes during catalysis are more sensitive to viscosity. Enzyme association seems to protect the more sensitive enzymes from viscosity-mediated inhibition. The association-mediated protection of the enzymes in a given metabolic pathway would constitute a new property of metabolons: that is, to enhance survival during stress. It is proposed that resistance to inhibition is due to elimination of non-productive conformations in highly motile enzymes.