Several approaches and technologies are currently available to study the glycosylated proteome (glycoproteomics) or the entire repertoire of glycans in a biological system (glycomics). The biological importance of glycosylation has driven the development of novel, sensitive separation and detection methods. New and improved methodologies, such as high throughput array systems and liquid chromatography-mass spectrometry for glycan profiling and sequencing, are emerging and are being applied in clinical research. A major thrust of glycoproteomics and glycomic clinical research is the application of these analytical tools to cancer research and is aimed at the discovery of glycan-based biomarkers for diagnosis of early stage human cancers, monitoring disease progression, measuring response to therapy, and detecting recurrence. The identification of cancer biomarkers requires a multidisciplinary approach and therefore this review discusses the strategies, technologies and methods currently used for N-glycoprotein/glycan biomarker research.