Honegger's oeuvre develops over extensive work phases that formulate specific themes: Tableau-Relief, Biseautage (panel paintings), Volume, Monoforme,Structure, Fragment (sculptures), Tableau-Espace and Artefact (wall objects). Honegger combines the rational principle of constructive art, such as logic and systematics, with the non-calculable components of empathy and spontaneity as well as randomness. The main themes of his work can be summarised as the synthesis of opposites, the investigation of colour (predominantly within monochrome), the figure and its fragments (circle and square) and the formulation of volume and space.
His main work as a painter began in the 1950s with an organically influenced abstraction (Sent, 1954), which became increasingly geometric around 1957. Under the titleTableau-Relief, the central painterly cycle of mostly monochrome, less often multicoloured, often multipart pictorial objects is still being created today. Until around 1980, Honegger preferred the collage technique for this; the lively texture and the delicate relief character of the pictorial objects are achieved by manually applying small cardboard plates to the canvas, which are painted in several glazed layers or treated with graphite pencil, creating a strongly light-reflecting, distinctly painterly-sensual surface (Tunic, 1960, Collage and Oil on Canvas, Jack Waser Collection, Zurich). In the 1980s, Honegger delved deeper into the investigation of the field of tension between a regular compositional grid and the so-called residual surface; a more pronounced relief as well as the expansion of the color palette with numerous unusual intermediate tones are the characteristics. In the 1990s, while keeping the circle and square form as a central theme, the focus was on a new pictorial language. Since then, this new series of tableaux reliefs has included large-format, neutrally painted two-part pictorial objects of the shaped canvas type, in which a circle and a square section usually collide (including the Reutlingen cycle of works, 1991-92).
The sculptural work is distinctly systematic and constructively oriented; in analogy to painting, it is based on individual themes and is almost exclusively in the context of art and the public or art in construction. Honegger defines this task in such a way that it must meet both aesthetic and social requirements and follow the idea of the "ecology of beauty". In the 1960s mainly wall reliefs in concrete (e.g. Wall Relief, 1968, Villmergen Schoolhouse), from the 1970s onwards increasingly fully sculptural works, usually composed in a regular system of several form segments. Preference for chromium steel and stone (granite, marble), whereby this is often used in combination with polished and unpolished surfaces, less often produced in aluminium or brass. From 1968 to around 1978 intensive study of the sphere and the spherical segment, evident in the cycle Volume (Volume 19, 1974, Chrome Steel, Collège Nevers; Volume 20, 1975, Polyester, Tulsa, Oklahoma, First National Tower). Parallel to this, work on variations and combinations of body fragments on the basis of an initially regular system under the title Structure (Structure 3, 1975-76, steel, painted, Université de Dijon). The mathematical basis is partially replaced or supplemented by the random method of finding forms (Structure 2, chrome steel and concrete, 1972, Zurich, ETH Hönggerberg, Alfred-Altherr-Terrasse), as it is also used in painting and drawing. Since the 1980s, the structure in the sculpture cycle Monoforme has been based on a single form or segment via layering and rotation (Monoforme 27, Homage to the Number 2, 1990-91, Granite, Adliswil-Zurich, Swiss Re); in the work sequenceDivision, from around 1988, the central theme is based on division, which determines both the construction and often the surfaces. In the 1990s, Honegger combined sculpture with color; through this and the common spectrum of forms, he approached the group of works in the Tableaux-Espaces. These large-format, usually vertically arranged wall objects, both single and multi-part, are based on sometimes simple, sometimes complicated combinations of forms and form the link between the painterly and the free-plastic work.
In addition to the picture and wall object and the freestanding sculpture, Honegger is also interested in drawing and, above all, in printmaking: he has a preference for unusual printing methods, for the publication of portfolio works, series and single sheets in deliberately small editions. In addition, he designs playful teaching aids (laying games, videos) for pedagogical lessons as well as exhibition concepts, journalism and art education. Honegger's artistic and social interest is thus manifested in a diverse practical and theoretical field of work; although it is based on periodic thematic changes, it is always based on holistically conceived cross-references within the media and activities. Up until his very last day, Gottfried Honegger was drawing and painting in his studio.