The green paper on constitutional development gives a comprehensive summary of the many proposals provided by different political parties and groups, as well as individuals and organisations from the community. It will help us find a consensus on the way forward for implementing universal suffrage. The existing method of electing the chief executive complies with Article 45 of the Basic Law, which says, 'the [chief executive] shall be selected by universal suffrage upon nomination by a broadly representative nominating committee in accordance with democratic procedures'. To increase broad representation, we support the idea of doubling the size of the existing 800-member nominating committee to 1,600. That could be done either by increasing the number of members from each sector, or by adding new sectors and expanding the electorate base of the nominating committee. A nomination threshold of 12.5 per cent of committee members would ensure candidates have wide support and real legitimacy. We are confident that current conditions in Hong Kong are favourable for implementing universal suffrage for choosing the chief executive. Functional constituencies have brought the voices of the business and professional sectors into the Legislative Council, making high-quality debates possible. Functional constituencies help Legco meet the interests of different sectors of society in a balanced way. Their contributions to the community are proven, and well-recognised by the public. Therefore functional seats should be retained, and reviewed in 2016. A universal suffrage system can be based on geographical or functional representation. In Hong Kong, some one-person-one-vote functional sectors - such as engineering - are often more cohesive, clear-cut and representative than the artificially created geographical districts. Functional representation provides balanced participation that promotes Hong Kong's development, so it should be viewed as a form of universal suffrage in line with international standards. Yim Kin-ping, fellow member, the Hong Kong Institution of Engineers