The most common challenges faced in the NES data collection process are:

• Lack of experience and / or planning to recruit experts. Each year a few Teams experience difficulties in finding suitable experts, possibly resulting from the dependence of the team on their personal contacts and by not using other means of sourcing. However, experience makes it easier to find suitable people to interview;

• Poor time management by the National Team. The NES schedule is well defined and there is more than sufficient time to conduct 36 interviews between March & July. However, some teams leave it too late to start the process and it is for this reason they encounter delays and hence difficulties in meeting the GEM deadlines;

• Size of population. In some countries, a small population creates difficulties in obtaining a sufficient number of experts. This is especially true when trying to conduct the survey after several years of participation in the GEM project. Again, experience helps to overcome this problem e.g. preparing a list of experts far in excess of what is required. This allows for cancellations, follow up for the next year etc. and helps to alleviate problems of not being able to do a sufficient number of interviews in the given time period.