Trypsin, the protease with well-defined specificity, offers a great potential as a biocatalyst in numerous biomedical and industrial applications. In this collection, the authors discuss preparation and performance of trypsin immobilized on polysaccharide-based carriers. Various methods by which trypsin can be physically or chemically immobilized have been discussed in respect to the carrier used and the application intended. The subsequent paper presents the results of monitoring TATI levels in 317 patients with endometrial cancer during treatment as well as final results during a 17-year follow-up period. 274% increase in TATI levels was found in patients with recurrence and distant metastasis diagnosed during the follow-up period after radical treatment. In the concluding work, traditional spectrophotometric and radioimmunoassay-based methods for trypsin activity assays are discussed and compared with the emerging sensors-based techniques for trypsin determination, such as electric, electrochemical, holographic, surface plasmon resonance, and QCM-based assays.