The kinetic progress of biopolymer gelation is measured in terms of the shear modulus-time curve available from mechanical spectroscopy. Attention is focused on the gel time, and on the limiting value of the modulus attained at long time. A theoretical treatment of these quantities is presented based on cascade theory. This model can take on a reversible, or irreversible, form depending on differential equations defining the growth of the degree of cross-linking alpha(t), i.e., depending on whether a crosslink equilibrium is assumed or permanent branched crosslinking competes with irreversible intramolecular cyclization. Application of this model to limiting modulus-concentration and modulus-temperature data is illustrated using results for a low DE pectin-calcium system. The model’s ability to explain modulus-molecular weight data is also demonstrated using literature data for kappa carrageenan gels. Where gel time-concentration data are concerned, success is much more limited, however, and this problem is discussed.