When a party is moving across steep, loose rocky ground (scree slopes) it is important that the party is spaced across the slope and that no one is moving directly above anybody else, to avoid the danger from falling rocks. Falling rocks can cause primary injury from an impact, or secondary injury as a result of someone moving too quickly out of the way and slipping or falling. If it is impossible for party members not to be beneath one another, then all should be as close together as possible. With large parties it may be necessary to move in smaller groups. If a rock or other object is dislodged and threatens others below, an immediate shout of ‘rock’ or ‘below’ is essential. Descending scree slopes efficiently is usually done best through a controlled slide, a bit like skiing, rather than trying to completely control every step. Ascending scree slopes is very tiring, and alternative routes should be sought if at all possible.