MPEJ Volume 10, No. 5, 45 pp. Received: Mar 2, 2004. Accepted: Mar 23, 2004. R. de la Llave, C.E. Wayne Whiskered and low dimensional tori in nearly integrable Hamiltonian systems ABSTRACT: We show that a nearly integrable hamiltonian system has invariant tori of all dimensions smaller than the number of degrees of freedom provided that certain nondegeneracy conditions are met. The tori we construct are generated by the resonances of the system and are topologically different from the orbits that are present in the integrable system. We also show that the tori we construct have stable and unstable manifolds and point out how to construct other types of interesting orbits. The method of proof is a combination of different perturbation methods. http://www.maia.ub.es/mpej/Vol/10/5.ps http://www.maia.ub.es/mpej/Vol/10/5.pdf http://www.ma.utexas.edu/mpej/Vol/10/5.ps http://www.ma.utexas.edu/mpej/Vol/10/5.pdf http://mpej.unige.ch/mpej/Vol/10/5.ps http://mpej.unige.ch/mpej/Vol/10/5.pdf