The Basic Law of the Hong Kong Special Administrative Region of the People's Republic Of China (HKSAR) is the constitutional document for the HKSAR. It enshrines the concepts of 'One Country, Two Systems', 'a high degree of autonomy' and 'Hong Kong People administering Hong Kong'. It also prescribes the various systems to be practised in the HKSAR.
The Basic Law consists of:
The full text of the Basic Law which comprises a total of nine chapters with 160 articles;
Annex I, which sets out the method for the selection of the Chief Executive of the HKSAR;
Annex II, which sets out the method for the formation of the Legislative Council of the HKSAR and its voting procedures; and
Annex III, which sets out the national laws to be applied in the HKSAR.
For commentary on the Basic Law, see the following books:
The Judicial Construction of Hong Kong's Basic Law: Courts, Politics and Society after 1997 by 
Law of the Hong Kong Constitution by 
Interpreting Hong Kong's Basic Law: The Struggle for Coherence by
The official versions of Hong Kong legislation are contained in the Hong Kong Government Gazette.