This volumecontainsthepaperspresentedattheSecondWorkshoponthePr- tical Applications of Declarative Languages (PADL 00) held in Boston, MA, USA, January 17{18, 2000. PADL 00 was co-located with the 27th ACM C- ference on the Principles of ProgrammingLanguages(POPL 00). The event was organized by COMPULOG AMERICAS. Declarativelanguagesbuildonasoundtheoreticalbasisto provideattractive frameworksfor application development. Indeed, these languages havebeen s- cessfully applied to vastly di erent real-worldsituations, ranging from data base management to active networks to software engineering to decision support s- tems, to mention a few examples. One major strength of declarative languages lies in the way work on e cient implementation has allowed programmers to take advantage of their strong theoretical foundations. In fact, new devel- ments in theory and implementation often open up new application areas. On the other hand, as declarative languages are applied to novel problems, a n- ber of interesting research issues arise. Well-known issues include designing for scalability, language extensions for application deployment, and programming environments. Thus, applications are both a cause for and bene t from progress in the theory and implementation of declarative systems. The goal of the International Workshop on Practical Aspects of Declarative Languages (PADL) series is to provide a forum where researchers, practiti- ers, and implementors of declarative languages may exchange ideas on current and novel application areas and on the requirements for eectiv e deployment of declarative systems. This volume contains the proceedings of the year 2000 workshop, held in Boston, Massachusetts, January 17{18, 2000. Thirty-six - persweresubmittedinresponsetothecallforpapers. Functional Programming.- First Class Patterns?.- Parallel Functional Reactive Programming.- Out-of-Core Functional Programming with Type-Based Primitives.- Functional-Logic Programming.- A Functional Logic Programming Approach to Graphical User Interfaces.- Using Static Analysis to Compile Non-sequential Functional Logic Programs?.- Logic Programming.- GNU Prolog: Beyond Compiling Prolog to C.- Heap Garbage Collection in XSB: Practice and Experience.- Implementation of a Linear Tabling Mechanism.- How to Incorporate Negation in a Prolog Compiler?.- Innovative Applications I.- A Logic-Based Information System.- HIPPO - A Declarative Graphical Modelling System.- Calculating a New Data Mining Algorithm for.- Constraint Programming and Constraint Solving.- A Toolkit for Constraint-Based Inference Engines.- CLIP: A CLP(Intervals) Dialect for Metalevel Constraint Solving.- Programming Deep Concurrent Constraint Combinators.- Labeling and Partial Local Consistency for Soft Constraint Programming.- Systems Applications.- Transformation-by-Example for XML.- Modeling HTML in Haskell.- A Logic Programming Approach to Supporting the Entries of XML Documents in an Object Database.- Innovative Applications II.- A Hybrid Approach for Solving Large Scale Crew Scheduling Problems.- Knowledgesheet: A Graphical Spreadsheet Interface for Interactively Developing a Class of Constraint Programs.- Invited Talks.- Current Trends in Logic Programming: Prospects and Promises (Abstract).- Production-Quality Proof-Carrying Code (Abstract).
