: Neighbor effects , that is the response on a given plot is affected by the treatments in neighboring plot and the effect by the treatment applied to that plot, are often showed by experiments in agriculture , horticulture , and forestry . Differences in height , root vigor or germination date for varieties may cause neighbor effects. As a result , the estimate of treatment differences may deviate because of this interference from neighboring plots . Neighbor-balanced designs ensure that the treatment comparisons will be as little affected by neighbor effects as possible . The allocation of treatments in these designs is such that every treatment occurs equally often with every other treatment as neighbors . circular block is a block in cycle form such that th treatments in the first and last plots are considered as neighbors. In circular block , each treatment has one left and other right neighbor . A collection of circular blocks in which any two treatments appear as neighbors at distance equal number of times is said to be -th order circular neighbor-balance design . These designs are divided into two groups, and are denoted by and \\\\ In this thesis, three different types of models (M1,M2 and M3) related to neighbor effects with independent observation are considered , In this thesis s ome methods to construction circular neighbor-balanced designs as method of cyclic shifts are considered. Also, optimality of these designs under M1, M2 and M3 are investigated. In the previouse researchs, method of cyclic shifts to construct has been used , the authors used this method to construct . Some series of and . are found by computer programming using in MATLAB software and method of cyclic shifts . Then, some of these designs witch are universally optimal under models M1 and M2 are identified .