A measure theoretical approach to quantum stochastic processes This monograph takes as starting point that abstract quantum stochastic processes can be understood as a quantum field theory in one space and in one time coordinate. As a result it is appropriate to represent operators as power series of creation and annihilation operators in normal ordered form which can be achieved using classical measure theory. Considering in detail four basic examples (e.g. a two level atom coupled to a heat bath of oscillators) in each case the Hamiltonian of the associated one parameter strongly continuous group is determined and the spectral decomposition is explicitly calculated in the form of generalized eigen vectors. Advanced topics include the theory of the Hudson Parthasarathy equation and the amplified oscillator problem. To that end a chapter on white noise calculus has also been included