Singapore's trio of political siblings introduced more than 20 years ago - the Non-Constituency MP, Nominated MP and group representation constituency (GRC) schemes - may be due for an update.
The NCMP scheme turns 32 this year. GRCs were born 28 years ago, and the NMP scheme, 26 years ago.
These innovations have allowed alternative views to be aired, and ensured minority communities are not shut out, said President Tony Tan Keng Yam on Jan 15.
But they have also run into some unanticipated trends along the way that Singapore's leaders could not have envisioned in the 1980s.
Insight looks at what the Government could address in its review.
The NCMP scheme, which offers parliamentary seats to the best-performing losing opposition candidates, was first introduced in 1984.
There is one stark difference between then and now.
No opposition candidate had won a seat in the 16 years between December 1965, when 13 opposition Barisan Sosialis MPs walked out of Parliament, and 1981. Then, vocal critics such as the late Workers' Party (WP) leader, Mr J.B. Jeyaretnam, said the scheme was an attempt to dissuade voters from electing opposition members.
But since the WP won five seats in Aljunied GRC and one in Hougang in the general elections in 2011 and last year, there have been six elected opposition MPs in the House. Ms Lee Li Lian's victory in the Punggol East by-election made it seven between 2013 and last year.
So today, the People's Action Party (PAP) is not the only party in the House.
But it is worth looking at whether this mechanism to ensure representation of alternative views in Parliament should remain or change with the political conditions of the day.
National University of Singapore (NUS) political scientist Reuben Wong is in two minds about it.
"In 1984, NCMPs came about because Singapore wanted to ensure alternative voices who would not be from the PAP. But the WP has won a GRC twice, so we don't really seem to need it any more.
"On the other hand, I'm not sure that the WP would continue to thrive without having NCMPs for exposure," he says, adding that the WP won Aljunied GRC last year "by the skin of its teeth" - 50.95 per cent of the vote share.
Another issue that appears to be coming to a head: the need for clearer public understanding about what happens when an NCMP seat has been declined.
The WP's Lee Li Lian turned down the seat offered to her for being the best performer among the losing candidates in the elections last year.
Party leaders have declared they want another of its office-holders, NUS sociology don Daniel Goh, to occupy the seat instead.
But it is not an automatic process that the next-in-line top losing opposition candidate is offered or entitled to the seat.
There has been no equivalent precedent for passing an NCMP seat within a party.
After the 1984 polls, the WP rejected the offer of an NCMP seat to its candidate M.P.D. Nair, who scored 48.8 per cent of votes in Jalan Kayu.
An offer was then made to the next-best loser, Singapore United Front candidate Tan Chee Kien, who also rejected it.
'DISASTER' FOR CHINESE
It would be a disaster for the Chinese community in Singapore if Singapore wakes up one day to find that we have an all-Chinese Parliament.
THEN DEPUTY PRIME MINISTER GOH CHOK TONG IN 1988, on the need to guarantee a multiracial Parliament.
Leader of the House Grace Fu has shed light on the procedure, and on Parliament's role in the process, now that Ms Lee has declined to take it up. Ms Fu has said that the WP has to file a motion in Parliament to declare the seat and to propose an alternative candidate for the NCMP seat.
The WP did so on Jan 15 and the expected debate on it this week will help shed light on the NCMP scheme and the stance of parties towards it.
Since the NMP scheme was first adopted in 1990, nips and tucks to its limits have been made.
In 1997, the maximum number of NMPs was raised from six to nine, its current limit, and in 2002, an NMP's term was extended from two to 21/2 years. The scheme was also made permanent in 2010.
What has not changed is its purpose: to offer Singaporeans more opportunities for political participation and to evolve a more consensual style of government where alternative views are heard.
IMPROVE SELECTION PROCESS
Singaporeans don't know the identities of those seeking to be appointed NMPs as Parliament does not make it public.
SINGAPORE MANAGEMENT UNIVERSITY LAW DON EUGENE TAN, a former NMP himself, who says the selection process can be made more robust, transparent and accountable.
Observers such as NUS political scientist Hussin Mutalib still point to the need to consolidate greater citizen participation in politics.
But the way of doing this is less clear. Does the NMP scheme continue to be an appropriate way of doing this, or is it becoming obsolete with the rise of the Internet?
Social media and other mechanisms for public feedback, such as national conversations and the government feedback unit, may have diluted the need for the presence of NMPs in the House.
Society has also become more diverse but the seven functional groups represented by NMPs (business and industry, the professions, the labour movement, social and community organisations, media, arts and sports, tertiary education institutions, and civil society) have not changed.
Are the groups in need of an update?
Singapore Management University law don Eugene Tan, a former NMP himself, says that the selection process can be made more robust, transparent and accountable.
Currently, different functional groups have different processes and rules on nominating applicants for consideration by the Parliament's special select committee.
"Singaporeans don't know the identities of those seeking to be appointed NMPs as Parliament does not make it public," he says.
But Parliament does benefit from having views and ideas put forth by MPs who are not bound by party positions and the party whip, says Assoc Prof Tan. The NMP scheme also enables sensitive issues to be raised in Parliament, he says, citing immigration and lesbian, gay, bisexual and transgender issues.
The main criticism of the GRC system is how much it has grown since it was set up in 1988. It began with 13 three-member GRCs. But the law was changed in 1991 and in 1996 to increase the maximum number of MPs per GRC from three to four, and then to six.
On one hand, leaders agree on the need to guarantee a multiracial Parliament. Said then Deputy Prime Minister Goh Chok Tong in 1988: "It would be a disaster for the Chinese community in Singapore if Singapore wakes up one day to find that we have an all-Chinese Parliament."
While this had not happened in Singapore, he made the case for amending the Constitution to exclude this possibility in the future. Such multiracial teams would also act as a check on candidates who may be tempted to play the race card and exploit communal sentiments in order to win votes, he added.
But larger GRCs were criticised for increasing the chances of rookie PAP candidates riding into Parliament on the coat-tails of heavyweight candidates in their team.
Opposition parties also said the GRC requirements made it harder for them to field teams.
Observers say that the guarantee of a multiracial Parliament can still be achieved with smaller GRC sizes.
Prime Minister Lee Hsien Loong has acknowledged as much, having pledged as early as 2009 to reduce the average number of MPs in a GRC from 5.4 to five, and to increase the number of single-member constituencies (SMCs). These changes were introduced in the 2011 General Election, when the number of SMCs was raised from nine to 12.
The latest boundary changes now bring the average number of MPs in each GRC to 4.75, down from anaverage of five in 2011.
Two six-man GRCs remain: Ang Mo Kio and Pasir-Ris Punggol.
Each has two members of a minority race on its team: Dr Intan Azura Mokhtar and Mr Darryl David in Ang Mo Kio GRC; and Mr Zainal Sapari and Dr Janil Puthucheary in Pasir Ris-Punggol GRC.
NUS' Prof Hussin said it is worth looking at further reductions to the number and size of GRCs.
This would let more individuals contest SMCs on the basis of merit, he said. It would also go some way towards consolidating meritocracy and multiculturalism in Singapore, he added.