WOTC - Protect against retrenchment

I asked this question in the Wisdom of the Crowd:

How can employees protect against retrenchment?

Here are the responses: (40 Votes)

38 % - Join a trade union and get the union to bargain collectively for retrenchment benefit.
35 % - Have personal saving to protect against loss of job.
20 % - Be more productive, so that the employer will find it difficult to get a replacement.
8 % - Retain some special knowledge as a bargaining chip.

See the pie chart at: 
http://www.wisdomofthecrowd.sg/chart.aspx?ID=1061