Within the framework of an irreversible aggregation model on a sample of polydimethyl diallyl ammonium chloride, we demonstrated that gelation occurred on a transient part from the autoacceleration stage until the dopolymerization stage. During part of the autoacceleration, the polymer solution was in a sol state on the segment of autoacceleration. Therefore, the use of the term gel effect in reference to the beginning of the reaction did not seem quite justified. (C) 2004 Wiley Periodicals, Inc.