Abstract. The problem of existence and uniqueness of polynomial solutions of the Lamé differential equationwhere A(x), B(x) and C(x) are polynomials of degree p + 1, p and p − 1, is under discussion. We concentrate on the case when A(x) has only real zeros a j and, in contrast to a classical result of Heine and Stieltjes which concerns the case of positive coefficients r j in the partial fraction decomposition B(x)/A(x) = p j=0 r j /(x − a j ), we allow the presence of both positive and negative coefficients r j . The corresponding electrostatic interpretation of the zeros of the solution y(x) as points of equilibrium in an electrostatic field generated by charges r j at a j is given. As an application we prove that the zeros of the Gegenbauer-Laurent polynomials are the points of unique equilibrium in a field generated by two positive and two negative charges.