Ground based observations of flares are reviewed to seek implications for a flare build-up on either a long or a short time scale. Plots of flare frequency and importance for certain individual centers of activity suggest a possible crescendo in flare occurrence days and hours before the development of large and significant flares. The X-ray records follow the same pattern of apparent build-up. A possible dependence between successive major flares, as phases one and two of a single complex flare event, suggests that the time scale in which the total flare event takes place may show extreme variation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43743/1/11207_2004_Article_BF00152264.pd
