The solution of large-scale ill-posed problems has recently received considerable attention. Many of the available solution methods are based on Tikhonov regularization. This talk surveys iterative methods for Tikhonov regularization. Several of these methods explore the connection between orthogonal polynomials, Gauss quadrature and Lanczos bidiagonalization. Methods for unconstrained and constrained regularization problems will be discussed and comparisons with other available iterative methods will be presented.