  In the Orientiworld framework the Standard Model fields are localized on
D3-branes sitting on top of an orientifold 3-plane. The transverse
6-dimensional space is a non-compact orbifold (or a more general conifold). The
4-dimensional gravity on D3-branes is reproduced due to the 4-dimensional
Einstein-Hilbert term induced at the quantum level. The orientifold 3-plane
plays a crucial role, in particular, without it the D3-brane world-volume
theories would be conformal due to the tadpole cancellation. We study
non-perturbative gauge dynamics in various N=1 supersymmetric orientiworld
models based on the Z_3 as well as Z_5 and Z_7 orbifold groups. Our discussions
illustrate that there is a rich variety of supersymmetry preserving dynamics in
some of these models. On the other hand, we also find some models with
dynamical supersymmetry breaking.
