Hiking with a group is different from hiking with one or two cars of people.
Hiking with a group means that if one person has to be evacuated by jeep or helicopter, 30 people also have to wait.
Therefore...please remember to bring and wear a hat, take the amount of recommended water, and make sure that visual contact between the front (guide) and the back ("rear guard") is not broken.
Hikers make sure to inform the tripmaster of any particular problem such as fear of heights, etc.
Tripmasters remember to make sure the guide advises in advance of any special features of the route.