However, we are only touching on a topic that will be explored in
some detail throughout the manual: what factors affect our choice
of a medium to get across a message? At this stage it will be enough
to make the point that one of our main considerations in communi-
cating a message is the decision about what medium-or combina-
tion of media-we choose.

The Occasion
Every act of communication takes place in a special situation-the
occasion. The occasion will involve three basic elements:
 the sender of the message;
 the receiver of the message;
 the relationship between the sender and receiver.
One ofKilonzo's messages was that if a storage basket is raised one
metre above the ground and air can blow freely through it, the
maize can be harvested early and left to dry effectively and safely
in the crib.
How well Kilonzo could deliver that message would depend on a
number of factors:
 Is he familiar enough with the subject to be
 convincing?
 Can he, for instance, work out how much grain and
 money the farmer would be losing by using his
 traditional methods of harvesting and drying?
 Can he give a realistic estimate of how much it
 would cost to raise the crib?
 When would the farmer reap the benefit of the
 expense?
In addition to the matter there is the manner:
 Can Kilonzo put his message across without
 criticizing or "putting down" the farmer?
 Does he have the confidence or the skill to start with
 a friendly chat and then let the conversation turn to
 the matters he wants to be raised?
 Can he let the farmer's problems and ideas be
 exposed before he offers his own solutions?