We present a lattice formulation of non-commutative Yang-Mills theory in arbitrary even dimensionality. The UV/IR mixing characteristic of noncommutative field theories is demonstrated at a completely non-perturbative level. We prove a discrete Morita equivalence between ordinary Yang-Mills theory with multi-valued gauge fields and non-commutative Yang-Mills theory with periodic gauge fields. Using this equivalence, we show that generic non-commutative gauge theories in the continuum can be regularized non perturbatively by means of ordinary lattice gauge theory with 't Hooft flux. In the case of irrational non-commutativity parameters, the rank of the gauge group of the commutative lattice theory must be sent to infinity in the continuum limit. As a special case, the construction includes the recent description of non-commutative Yang-Mills theories using twisted large-N reduced models. We study the coupling of non-commutative gauge fields to matter fields in the fundamental representation of the gauge group using the lattice formalism. The large mass expansion is used to describe the physical meaning of Wilson loops in non-commutative gauge theories. We also demonstrate Morita equivalence in the presence of fundamental matter fields and use this property to comment on the calculation of the beta-function in non-commutative quantum electrodynamics.correspondence has been used to suggest that non-commutative geometry provides a natural framework to describe non-perturbative aspects of string theory [2,5]. This belief is further supported by the fact that Matrix Theory [6] and the IIB-matrix model [7], which are conjectured to provide non-perturbative definitions of string theories, give rise to non-commutative Yang-Mills theory on toroidal compactifications [8]. The particular non-commutative toroidal compactification is interpreted as being the result of the presence of a background Neveu-Schwarz two-form field, and it can also be understood in the context of open-string quantization in D-brane backgrounds [9, 10]. Furthermore, in ref. [11] it has been shown that the IIB-matrix model with D-brane backgrounds is described by non-commutative Yang-Mills theory.The early motivation [12] for studying quantum field theory on non-commutative spacetimes was that, because of the spacetime uncertainty relation, the introduction of non commutativity would provide a natural ultraviolet regularization. However, more recent perturbative calculations [13]- [16] have shown that planar noncommutative Feynman diagrams contain exactly the same ultraviolet divergences that their commutative counterparts do, which implies that the non commutativity does not serve as an ultraviolet regulator. One therefore needs to introduce some other form of regularization to study the dynamics of non-commutative field theories. On the other hand, it has been found that the ultraviolet divergences in non-planar Feynman diagrams [16,17] exhibit an intriguing mixing of ultraviolet and infrared scales, which can also be described using string-theoreti...