  In this work, we present a consistent Hamiltonian analysis of cosmological
perturbations at all orders. To make the procedure transparent, we consider a
simple model and resolve the `gauge-fixing' issues and extend the analysis to
scalar field models and show that our approach can be applied to any order of
perturbation for any first order derivative fields. In the case of Galilean
scalar fields, our procedure can extract constrained relations at all orders in
perturbations leading to the fact that there is no extra degrees of freedom due
to the presence of higher time derivatives of the field in the Lagrangian. We
compare and contrast our approach to the Lagrangian approach (Chen et al
[2006]) for extracting higher order correlations and show that our approach is
quick and robust and can be applied to any model of gravity and matter fields.
