NB: for a good library of general purpose data-structures, I (actually Fare Rideau) recommend cl-containers if you want stateful (imperative) variants, or lisp-interface-library if you want pure (functional) variants. If you implement more data-structures, we recommend you extend their respective interfaces. For more specialized data-structures, read on.

• access - Access is a library to ease getting and setting values in nested dictionary-like objects by providing a unified interface to hash-tables, clos-objects, plists and alists
• array-operations - Array-operations provides commonly used operations on arrays
• avl-tree - AVL (Adelson-Velsky-Landis) Tree is a self-balancing binary search tree implementation in Common Lisp
• binomial-heap - Binomial-heap is an implementation of the binomial heap data structure
• bk-tree - This page is moved to https://github.com/vy/bk-tree
• bknr-skip-list - bknr-skip-list is an implemetation of skip list data structures for bknr
• cdr_assoc - A setf method for (cdr (assoc ...)), at google code: cdr-assoc
• cl-btree - B-Tree implemented in Common Lisp
• cl-custom-hash-table - cl-custom-hash-table extends the hash table data structure by allowing the use of arbitrary TEST/HASH functions, in addition to the TEST functions allowed by the standard (EQ, EQL, EQUAL and EQUALP)
• cl-geo - cl-geo is a geospatial library, providing a set of geographic data structures and operations
• cl-heap - CL-HEAP implements the binary heap, Fibonacci heap, and priority queue data structures
• cl-treemaps - cl-treemaps is a lightweight and fast implementation of binary trees
• data-table - data-table is a library providing a data structure that has rows of data and column names and types (ie database results)
• dawg - DAWG is a DoubleArray/Directed Acyclic Word Graph data structure implementation
• dict - DICT is a hash table implementation
• dlist - dlist is a simple, portable Common Lisp implementation of the double linked list (a very common data structure)
• dlist (KD) - dlist - A Common Lisp library that implements doubly-linked lists
• Dynamic ADTs - Dynamic ADTs are abstract data types with a framework for observation and adaptation
• Flexichain - Flexichain is an API for editable sequences
• FSet - FSet is a functional set-theoretic collections data structures library by _(Scott L
• Funds - Funds provides portable, purely functional data structures written in Common Lisp
• genhash - NET HEXAPODIA HASHTABLES is a data structure library for generic hash tables
• heap - Heap provides two priority queue implementations in common lisp; a simple linked list and a Fibonacci heap
• Heresy - Heresy is an implementation of the lazy list data structure
• hh-redblack - hh-redblack provides in-memory and disk-based red-black trees
• jarw-dictionary - jarw-dictionary is a generic map/dictionary interface with implementations using internal hash-tables, property lists, files and directories including in-memory caching
• jpl-queues - jpl-queues implements a few different kinds of queue data structures
• lisp-interface-library - lisp-interface-library is a collection of pure and stateful data structures in interface-passing style from Fare Rideau
• minheap - minheap provides several heap data structures with meldable min-heap and priority queue functionality
• nary-tree - The n-ary-tree package implements an automatically rebalancing B-tree data structure which supports n >= 5 items in any mixture of types per node
• patty - Patty is a library that facilitates working with functional data structures on top of CLOS
• pipes - pipes implements the input stream (lazy list) data structure
• quick-arrays - Quick arrays is an old data structure hack that is still useful: it simulates slow N-dimensional arrays using the faster 1D arrays
• Red-Black-trees - Red-Black-trees is an implementation of red-black-trees (a data structure)
• ropes - ropes is an implementation of the rope data structure, an alternative to strings with more efficient concatenation
• SEMI-PRECIOUS - SEMI-PRECIOUS is a library of algorithms/data structures
• Series - Series is a library for operating on series, a data structure similar to a sequence
• spatial-trees - spatial-trees is a set of dynamic index data structures for spatially-extended data
• symbol-namespaces - symbol-namespaces defines a new kind of package that's named by a symbol rather than a string and that maps from existing symbols to their respective "implicitly managed" counterparts
• TREES - TREES provides several binary tree data structures exposed through a uniform CLOS interface
• X.FDATATYPES - XFDATATYPES implements 3 functional data structures: