Chemistry and Partial Order -- Partial Ordering of Properties: The Young Diagram Lattice and Related Chemical Systems -- Hasse Diagrams and their Relation to Molecular Periodicity -- Directed Reaction Graphs as Posets -- Environmental Chemistry and Systems -- to partial order theory exemplified by the Evaluation of Sampling Sites -- Comparative Evaluation and Analysis of Water Sediment Data -- Prioritizing PBT Substances -- Quantitative Structure Activity Relationships -- Interpolation Schemes in QSAR -- New QSAR Modelling Approach Based on Ranking Models by Genetic Algorithms - Variable Subset Selection (GA-VSS) -- Decision support -- Aspects of Decision Support in Water Management: Data based evaluation compared with expectations -- A Comparison of Partial Order Technique with Three Methods of Multi-Criteria Analysis for Ranking of Chemical Substance -- Field, Monitoring and Information -- Developing decision support based on field data and partial order theory -- Evaluation of Biomonitoring Data -- Exploring Patterns of Habitat Diversity Across Landscapes Using Partial Ordering -- Information Systems and Databases -- Rules and Complexity -- Contexts, Concepts, Implications and Hypotheses -- Partial Orders and Complexity: The Young Diagram Lattice -- Historical remarks -- Hasse Diagrams and Software Development -- Introductory References -- Introductory References.