Accession negotiations describe the time frame given for Turkey to fully and effectively adopt the EU acquis to her own legal system

The EU acquis refers to the total body of the EU law. It is composed of roughly one hundred and twenty thousand pages.

It contains the treaties on which EU was formed, the changes to these treaties, the treaties that the previously accessed countries signed and the legislation enacted by the EU Commission, EU Council, European Community and EU Court of Justice.

The EU acquis has been categorized under 35 chapters . These chapters are as follows;

1) Free Movement of Goods
2) Free Movement of Workers
3) Right of Establishment and Freedom to Provide Services
4) Free Movement of Capital
5) Public Procurement
6) Company Law
7) Intellectual Property Law
8) Competition Policy
9) Financial Services
10) Information Society and Media
11) Agriculture and Rural Development 
12) Food Safety, Veterinary and Phytosanitary Policy
13) Fisheries
14) Transport Policy
15) Energy
16) Taxation
17) Economic and Monetary Policy
18) Statistics
19) Social Policy and Employment
20) Enterprise and Industrial Policy
21) Trans-European Networks
22) Regional Policy and Coordination of Structural Instruments
23) Judiciary and Fundamental Rights
24) Justice, Freedom and Security
25) Science and Research
26) Education and Culture
27) Environment
28) Consumer and Health Protection
29) Customs Union
30) External Relations
31) Foreign, Security and Defense Policy
32) Financial Control
33) Financial and Budgetary Provisions
34) Institutions
35) Other Issues

The accession negotiations have begun with the first stage of the process, “screening”. The main contributors to this process are Turkish bureaucrats and the EU Commission members. The main purpose of screening is to speed up the accession process. It is the process in which information on the legislation under the acquis is provided, the differences between EU legislation and legislation of the candidate country is determined, and a broad calendar of the accession process and the potential obstacles that may get in the way of this process are determined.

Shortly after the EU Accession Negotiations was launched on 3 October 2005, Screening Process was started with a meeting on the Chapter “Science and Research” on 20 October 2005. Screening Process for all negotiation Chapters was completed on 13 October 2006.

Upon the completion of the screening process for a given chapter, the EU Commission provides the member States a screening report. The assessments and propositions in this document play the vital role of determining whether the chapter is ready to be opened. In these reports the EU commission reviews the information given by Turkey during the screening process and according to this information decides whether Turkey is ready for the opening of the specific chapter. At the end of this document the EU Commission either suggests the opening of the chapter according to the given information or it presents opening benchmarks to be fulfilled in order for this chapter to be opened.

Source: http://www.ab.gov.tr/index.php?p=37&l=2