A study of two types of high efficiency gas chromatographic columns was conducted. The first type (micropacked) can be defined as columns having an internal diameter less than 1 mm and a particle/column diameter ratio between 0.1 and O.3 and a packing density comparable to conventional packed columns. The second type, slurry packed gas chromatographic columns can be defined as columns which are prepared by using high liquid pressure to rapidly pass a stable suspension of small diameter packing material into the column. This procedure packs small particles more homogeneously and more efficiently. The standard procedure for preparing micropacked columns was evaluated and modified to increase the reproducibility of the technique. Different methods of preparing the packing materials were investigated. Parameters such as particle size, column length, and sample size were studied. Slurry packing techniques which are commonly used for the preparation of high efficiency LC columns were adapted for preparation of GC columns. A study was made to determine optimum particle size for maximum efficiency in gas chromatographic columns. Columns prepared by conventional diy packing technique were compared to columns packed using the slurry packing technique to determine reproducibility of packing technique and column efficiency. Slurry packed columns were used in both LC and GC modes. A study was made to determine the effect of column diameter, column length, column temperature, and sample capacity on efficiency. Applications for slurry packed gas-solid adsorption columns were studied. This method of slurry packing GC columns increased the efficiency by as much as five-fold over values previously reported. Results of the study indicated that optimum particle diameter was 53 μm - 63 μm with an optimum column diameter of 9.9 mm. The results of column temperature studies indicate the minimum column temperature compatible with the sample being analyzed should be used for maximum efficiency. / Ph. D.