The study of the large-scale structure in the universe places tight constraints on theories of galaxy formation. On scales greater than 10h^-1Mpc, the conditions in the early universe should still be imprinted on the large-scale structure we see today. However, these studies have been hampered by the lack of a reliable, homogeneous catalogue of galaxies and clusters of galaxies over a large area of the sky. Previous catalogues have been built from visual scans of photographic plates (e.g. the Lick galaxy catalogue and the Abell cluster catalogue) and many authors believe the large-scale structure seen in these catalogues is an artifact of the subjective manner in which they were constructed. This thesis is concerned with the scientific analysis of the Edinburgh/Durham Southern Galaxy Catalogue (EDSGC), the Edinburgh/Durham Cluster Catalogue (EDCC) and the Edinburgh/Milano (EM) cluster redshift survey. The first of these databases was objectively constructed from COSMOS scans of 60 UK Schmidt IIIa-J survey plates and contains 1.5 million galaxies covering over 1500 degrees square of the sky centred at the South Galactic Pole. The EDSGC is therefore, ideal for studying the large-scale structure in the universe free from the criticisms levelled at previous catalogues. The other two databases were constructed from the EDSGC and are described in detail in this thesis. The EDCC was constructed from the EDSGC using a peak-finding algorithm to locate the galaxy overdensities, followed by a pseudo-Abell style analysis to classify the clusters. In total, 737 groups or clusters were detected and the EDCC was found to be complete to a limiting magnitude of m₁₀(b_j) = 18.75 (z = 0.13). When compared to the Abell catalogue over the EDCC area, over 80% of the Abell clusters were found in the EDCC to the completeness limits of both the catalogues. However, only 50% of the EDCC clusters, to the respective completeness limits, were found. The EM survey was constructed from the EDCC and consists of 103 cluster redshifts, each with an average of 10 galaxy redshift measurements. Over 70% of the clusters were found to have some level of interloper contamination and ~ 10% of the clusters were defined as spurious. These figures are much higher than previously thought. From the EM survey, a 90% redshift complete sample of cluster was selected using an Abell radius of 1.0h^-1Mpc.