Longitudinal data that track the course of disability and well-being are being collected for older populations, with remeasurements taken at annual or longer intervals. These can miss much of the genuine dynamics that older people experience. This analysis uses a data set with fine-grained data on health and function. It involves 165 persons ages 55 and over who were followed for minimum of 1 year (up to 2 years) after hospitalization for a chronic condition (six of which were specified). Within that period, each person had nine separate contacts for assessment of cognitive, physical, social, and emotional function. Respondents also kept health diaries continuously for a year. This article reports patterns of change for the diaries only, focusing on two items recorded daily: self-rated health and activity level. We analyze the data visually, by plots of these items over time for each person, and statistically, by numerical indicators of changes and levels for the items. Differentials in changes and levels by patient characteristics (e.g., age, sex, marital status, diagnosis) were explored. Most people experience a posthospital improvement, with the majority attaining their usual levels of well-being and activity, despite their serious illness. But this recovery is usually interrupted by episodes of low well-being and activity and even further hospital stays. Statistical analyses show that, overall, physical health suffers a small decline over the year whereas activity levels tend to improve. Health is worst and activity levels lowest, gains are smallest and declines largest, for elderly (ages 75 and older) men and for nonmarried people, especially men. Together, the visual and statistical analyses confirm the profound dynamics in health and function that middle-aged and older people with chronic conditions experience.