Apparently don't bother doing anything as absurd as actually applying for one on their website. From the DevEx LinkedIn forum:
SK: Is there anyone in this group who was successful in getting an assignment by applying in the UNDP website?
GP: Not so far. I was working in Kabul earlier this year, and was then invited to fill out the paperwork to join a pre-approved list of consultants.
SK: Ya that's what I thought. I don't think anyone ever gets a job through that website. It is such a ripoff. The World Bank is far more transparent and fair in employing consultants.
TN: I feel that a proportion of the advertised roles are already filled by the previous incumbent. It is possible that their contract is up for renewal and UN rules require that the position be advertised. I hope I'm wrong, but this process puts an awful lot of people to an unnecessary inconvenience, and for nothing.
SK: Also they need a minimum number of application to go through the process. I'm told that sometimes people do get through the website. So do apply, except that it is such a laborious process.
JE: I think it is a waste of time and energy applying for many of these postions with UN and ADB as well. People are already in place and the advertisement is to provide the appearance of an open selection process. Unless 'invited' to apply for a specific postion, I personally won't waste my time.
JML: I worked as a Programme Officer for UNDP Timor-Leste for 3 years and then had a short-stint in the regional office in Bangkok. I then took a break for motherhood and for the past year have been applying to get back in the game. It is hard. I agree with TN’s post and sadly know it is the case for some of the vacancies.
SM: I agree to the comments, UNDP must think of refining the process,if they want to keep the already working people, at least they must not waste others time and resources.
This a double tragedy that they raise a hope for jobless, waste their time and unnecessiarly to show fairness,which in reality .....................they may tell it better.
SK: Thanks for your responses. I recently wrote to UNDP to highlight some of the anomalies in the application process. For example a lot of jobs will ask for a financial proposal, except that there is no scope in the application format to provide one. The motivation section does not accept more than 1000 characters!