An in-person meeting will greatly increase your chance of success. This initial contact may be the first opportunity to begin to define the problem. Clearly state why you are inviting individuals and organizations to attend, including logistical information, such as the meeting agenda, time, location, and directions. Know what outcome you are hoping to obtain from this meeting.
If you are to be successful, you will need a solid core of committed people who have some degree of passion for the cause. If that passion and commitment is lacking, you may need to regroup, find additional partners, and/or seriously review whether the data you presented truly tell the story of the urgent need for action within your community.