Recruiters find people for jobs, not jobs for people
This is probably the best piece of advice I can provide, to help you understand how to deal with recruiters/employment agencies/search firms – Recruiters find people for jobs, not jobs for people. In other words – recruiters are hired by companies, to find people for specific jobs. They are not in business to help you find a job and you are not their client.
So when getting in touch with recruiters as part of your job search, make sure you state your interest for positions which are a very good match for your past experience/education. That will help you get more success from your dealings with them.
It is also good to remember that relationships are important - People help people they like and know. Therefore, I would suggest calling a recruiter, after you have sent them your resume. The purpose of the call is to start developing a relationship with them and to get on their radar. Ask them when is a good time for you to explain your candidacy in more detail and let them know why you are well suited for particular roles you are applying to. In conversations with people in Singapore, I often hear that the recruiters here are rude, never call back, cancel/delay meetings and so on. Sure, some might be like that but not all. So I would still recommend getting in touch with recruiters because you will have success with a few and they can be a good ally during your job search.
Have had positive/negative experiences with recruiters in Singapore? Do leave a comment with information about what you faced and which recruiters to approach/avoid.
Sources and references: Sandbox Advisors



