George Jakab, now a tenured professor at the Johns Hopkins School of Hygiene and Public Health, was then only a young, up-and-coming researcher hoping to make his mark in the world. Confused, he went to Gareth Green and said, "What's this all about?" For years, Jakab and Green had been working side-by-side as lung disease researchers. When their lab published results, it was routine: the paper would have both their names on it as authors. But strangely, on this one Green had crossed his own name out.

"It is time for you to go out and let the world see that you are independent," Jakab recalls Green saying. "This was your idea. It is time for you to publish a paper without my name on it." Jakab adds, "In this world of publish or perish, that little incident had a big impact on me."

That kind of "little incident" of gentle guidance and selflessness was typical of Associate Dean Gareth Green's brilliant 40-year career as a pulmonary disease researcher and academic administrator. Green was widely admired for being an incisive thinker and investigator who had a deft, understated talent for bringing out the best in colleagues and students. As a scientist, Green was one of the first researchers to recognize that cellular-level systems in the lungs, particularly cells called alveolar macrophages, play a pivotal role in protecting the lungs against infection and other injury. As an administrator, he created a ground-breaking pulmonary disease treatment network among Vermont's hospitals; chaired Johns Hopkins' prestigious Department of Environmental Health Sciences for 14 years; and strengthened the School's M.P.H. program as associate dean for professional education, until retiring in June because of the brain cancer that he died from on July 18 at the age of 67.

With a national reputation as a first-rank health researcher, Green was tapped to head up several key committees, including the National Institutes of Health's panel on Gulf War Syndrome. Green took the position that there was evidence of biological illness to the syndrome that was aggravated by psychological conditions.

Green was a subtle but effective leader according to friends and colleagues. Acting Dean James Ware says, "In an environment dominated by type-As and people competing for air time, Gareth was really willing to listen and evaluate other people's points of view."

Green grew up in the Corey Hill section of Brookline and graduated from Boston Latin High School, Harvard College, and Harvard Medical School. His father was Robert Montraville Green, a Harvard Medical School anatomy professor, and his family tree features five successive generations of Harvard faculty, going back to Henry Ware Sr., a divinity school professor in the early 1800s.

As a young investigator in the early 1960s, Green was drawn to pulmonary disease because of a mysterious and disturbing fact: World War II veterans were getting very sick and even dying from what should have been relatively mild cases of bronchitis and pneumonia. It was a pattern that the veterans were suffering from some kind of immunological deficit. Working in the Channing Laboratory when it was located in the Boston City Hospital, Green and his colleagues conducted a series of novel experiments that involved individually wrapping white Swiss mice in little rubber mesh bags and then exposing them in an airtight chamber to a "bacterial cloud." The animals were then killed and their lungs inspected for signs of infection.

Until Green's work, research on the lungs' defenses had concentrated on the mechanical action of the mucociliary transport system, which consists of tiny, hairlike cilia and mucus that push bacteria and other foreign matter up and away from the delicate tissue of the lungs. But Green zeroed in on how the lungs handle infectious particles at the cellular level--and he had the field pretty much to himself. "No one was looking at the biology of the lung," he said in an interview several weeks before his death. Using radioactively tagged bacteria, Green was able to show that the bacteria were killed in the lungs and not just brushed away by the mucociliary system.

Starting with two papers in 1964 that he coauthored with Edward Kass, the legendary founder and head of the Channing Lab, Green started to assemble a fat dossier characterizing the alveolar macrophage, the large immunological cells that patrol the minuscule, saclike alveoli of the lungs. Jakab notes that when Green started his research career, there were maybe a total of 100 published papers on alveolar macrophages. Now they number in the tens of thousands. "He was the investigator who promoted the importance of the alveolar macrophage," says Jakab. At a faculty meeting last spring when Green's retirement was officially announced, Joseph Brain, Cecil K. and Philip Drinker Professor of Environmental Physiology and chair of the Department of Environmental Health, said that Kass and Green's papers on the bactericidal activity of alveolar macrophages were "real citation classics." Moreover, their experimental techniques had staying power, as they were used to investigate the effects of ozone, smoking, surgery, and other environmental influences on lung health.

Green left Boston for Burlington, Vermont, in 1968 to take a position at the University of Vermont Medical Center. His research took on an epidemiological bent there when he started to investigate why so much lung disease occurred in such a bucolic place. Scratching beneath the surface of all that beautiful scenery, Green found that some farmers were getting sick from breathing in moldy spores when they baled wet hay, while workers in small, often unregulated manufacturing operations were inhaling dirty, unventilated air. To improve the medical treatment of lung disease, Green orchestrated the creation of a statewide network of pulmonary medicine clinics, with the university's medical center serving as the hub. "That is when I got trained in getting people to work together," said Green. "It was one of the funnest things I have ever done."

Partly because he was frustrated by a shake-up at the medical center that virtually eliminated the Department of Community Medicine--and with it the medical center's public health focus--Green moved to the Johns Hopkins School of Public Health in 1976 as professor and chair of the Department of Environmental Health Sciences. Green had the unenviable task of running a large department recently created by merging three separate departments. But Green successfully counteracted the tendency for faculty to pursue their own agendas, based on their interests, departmental pedigrees, and funding sources. Jakab says, "He got us working together, shepherding us toward common interests. That is what I miss most about him."

When Green came to the School in 1990, it was very much a question of coming home. Green said he and his wife, Joanna, liked Baltimore and Maryland, "but it just didn't feel like home." Joanna Green's father had bought a summer home on Lake Winnipesaukee in New Hampshire in the 1940s that Green and his wife expanded and remodeled. Green enjoyed sailing a small catboat and driving a classic, wooden Chris-Craft runabout. Green said that having the house on the lake in New Hampshire the past 40 years has been "something stable in a life that has been fairly itinerant."

As associate dean for professional education, Green was put in charge of the School's M.P.H. program, whose administrative structure had been revamped shortly before Green's arrival. Department-by-department control of the program was replaced by a more centralized administrative set-up, with students choosing areas of concentration relating to the practice of public health. It fell to Green to make this new structure work. From a practical standpoint, this meant convincing faculty to give the M.P.H. program time and attention. "It was tough, but I think we moved it forward," said Green, who credited Alec Walker, chair of the epidemiology department, and Marcello Pagano, a biostatistics professor, with being especially supportive and helpful. During his eight years at the School, Green also helped establish the Center for Continuing Professional Education and the Division of Public Health Practice. In addition, he taught the introductory environmental health course.

Roberta Gianfortoni, who as director of professional training worked closely with Green at the School, says what she will remember most about Green was his steadying, kind presence. "There was just something so humane, so decent about him. Those qualities are harder and harder to find these days."