As a result of colonialism, pidgins and creoles emerged around the world in order to fulfil the communicative needs of the people who came in contact in the new situation. As those needs disappeared pidgins also gradually disappeared. However, in some areas, such as Papua New Guinea, the need for a common language in such a linguistically heterogeneous society helped the impoverished pidgin evolve into an extended pidgin suitable for use in a wide range of contexts and functions. This dissertation analyzes the parallel developments of Tok Pisin and the history of its speakers, from the birth of the pidgin as a jargon in the Southwest Pacific until the present moment, when as an extended pidgin with a few thousand creole speakers, faces the challenge of adapting to the modern world. In Chapter I some basic considerations are made about the circumstances that allow pidgins and creoles to emerge and the strategies used in their formation and further development. After this introduction to the topic, attention is paid to the relevant events taking place in the southwest Pacific first and in Papua New Guinea later, namely labour trade and plantations, the declaration of a German protectorate in 1884, the changing of colonial powers, World War I and World War II and the current sociolinguistic situation in the country. In Chapter II a diachronic analysis is made of the developments taking place in the different areas of Tok Pisin. During the jargon stage Tok Pisin was used basically for communication between colonizers and natives. There is a need to communicate in a very restricted domain only, communication is very simple and the degree of individual variation is likely to be very high in all the areas of the language. During stabilization norms emerged out of the chaos of the jargon. It was during this stage that Tok Pisin started to be used for communication among natives rather than only between colonizers and natives. When indentured labourers, speakers of different languages, came together on plantations, they soon realized they needed to communicate. The urgent need for vocabulary in the new situation was fulfilled by borrowing from all sources at hand, e.g. English, German, Malay, Tolai. During expansion, Tok Pisin made use of internal resources and expanded the possibilities already present in the language. At the end of this stage, renewed contact of Tok Pisin with English in towns caused a new variety to emerge, Urban Pidgin, characterized by the massive borrowing from English. In Chapter III the focus is on different aspects of the lexicon which will show how Tok Pisin has adapted to its new uses and functions in a new social environment. Tok Pisin is not a language for restricted communication anymore, its use has greatly expanded and, as a consequence, its functions, too. On the one hand, there has been a massive increase of its inventory of lexical items necessary to adapt the language to the new circumstances of the society where it is spoken. New words which deal with new situations have been incorporated from English. On the other hand, stylistic variation is now possible, and a number of changes do not have an influence on the referential power, but rather on style. Tok Pisin has been enriched by new functions including expressive and poetic. Lexicon seems to be affected by external influences earlier than the other areas of the language. Speakers of Tok Pisin seem to be favouring borrowing over exploitation of internal resources. Also in grammar, although to a much lesser extent, these changes can be observed. What evidence shows at the present moment is that the new patterns being borrowed do no seem to be replacing the old ones, but rather both of them coexist. Thus, instability will be a feature of the language while restructuring takes place. This can show that a linguistic continuum might be consolidating and that there might be a range of possibilities within the spectrum to convey the same idea. The gap emerging in the language is a reflection of the changes taking place in society, being caused by different degrees of access to formal education and to an urban setting. As a consequence of the changes taking place in society, the use of loanwords from the substratum is also declining, because they reflect a reality that is gradually disappearing. Only those words whose referent is still present will remain. Also idioms which correspond to a certain interpretation of reality will tend to disappear as the Western culture and beliefs spread. An area where substratum influence tends to be retained longer is exclamations and interjections. However, even here English expressions are finding their way into Tok Pisin. At the present moment very few people in Papua New Guinea are in direct contact with English. And for many it is a language learnt in the formal environment of the classroom. The influence of English on Tok Pisin will not spread if Tok Pisin remains only the language of formal education. However, other factors such as the contact of a growing number of speakers with English as a consequence of expected migration to town areas, the influence of the media or the growing prestige of the urban variety can help to increase the number of English features in Tok Pisin. Throughout its history, Tok Pisin has evolved and has become enriched by its speakers. They, rather than language policies, have been the ones who have decided the direction of the development of the language by accepting or rejecting the different possibilities of expansion. It is in their hands to decide what Tok Pisin will be like, to decide if they want to favour the changes in the direction of English and the consolidation of a linguistic continuum already emerging, knowing there is a risk of losing communicative power, a factor which cannot be undervalued in such a linguistically heterogeneous society. __________________________________________________________________________________________________ As a result of colonialism, pidgins and creoles emerged around the world in order to fulfil the communicative needs of the people who came in contact in the new situation. As those needs disappeared pidgins also gradually disappeared. However, in some areas, such as Papua New Guinea, the need for a common language in such a linguistically heterogeneous society helped the impoverished pidgin evolve into an extended pidgin suitable for use in a wide range of contexts and functions. This dissertation analyzes the parallel developments of Tok Pisin and the history of its speakers, from the birth of the pidgin as a jargon in the Southwest Pacific until the present moment, when as an extended pidgin with a few thousand creole speakers, faces the challenge of adapting to the modern world. A further analysis of different aspects of the lexicon shows how Tok Pisin has greatly expanded its use and functions. English seems to be influencing Tok Pisin to a great extent in the area of lexicon and, to a lesser extent in other areas as well. What evidence shows at the present moment is that the new patterns being borrowed do not seem to be replacing the old ones, but rather both of them coexist. Thus, instability will be a feature of the language while restructuring takes place. Social mobility and education will be important factrs that will make speakers modify their speech in the direction of the standard. Some hypotheses about the possible further developments of Tok Pisin are suggested.