Using an instability problem as the basis, Gammelsr¿d (1975) developed a rationale for Langmuir circulation. By means of a solution that is valid even for the nonlinear system, the proposed problem is reexamined from a more general point of view, including conditions or restrictions on the mean flow variables and scales, and it is found that, although the instability is possible, it is not particularly applicable to the situation envisioned. Salient other possibilities with respect to the stability for this important model are also discussed.