Part I: Introductions -- The proof of the pudding -- Interlinguistics - its aims, its achievements, and its place in language science -- Part II: Planned Languages in Linguistics -- Ethnic language and planned language -- Planned languages - a survey of some of the main problems -- Interlinguistics: a branch of applied linguistics? -- Part III: Language Design and Language Change -- Principles for constructing Planned Languages -- Optimization in language planning -- A few notes on the evolution of Esperanto -- Part IV: Sociolinguistics and Psycholinguistics -- Linguistic artificiality and cognitive competence -- Who are the speakers of Esperanto? -- Planned auxiliary language and communicative competence -- Part V: The Language of Literature -- Planning nonstandard language -- If Shakespeare had written in Esperanto -- Part VI: Grammar -- Degree words in Esperanto and categories in Universal Grammar -- An unplanned development in planned languages -- Part VII: Terminology and Computational Lexicography -- Terminological standardization - its roots and fruits in planned languages -- Terminics in the interethnic language -- Knowledge-driven terminography for machine translation -- Index.