This paper develops an analytical model to calculate the amount by which individuals are expected to modify their values (the relationship between lifestyle and happiness, as measured by subjective well-being, SWB) and to adopt innovative technologies (to increase the sustainability of production and consumption, measured by the ecological footprint, EF) to allow current and future generations to achieve sustainable happiness (the pursuit of happiness that does not exploit other people, the environment, or future generations). The paper also examines the dependence of these changes on an individual's concern for future generations and on their country's current state of economic development. It is shown that individuals in better-off developed countries and individuals in worse-off developing countries can achieve sustainability with a reasonable level of value change (0-30 %) and a feasible degree of technological innovation (10-40 %), respectively. In contrast, individuals in better-off developing countries and individuals in worse-off developed countries must rely to an impractical degree of technological innovation (50-70 %) and to an unreasonable level of value change (40-70 %), respectively. Finally, individuals in developing countries differ from individuals in developed countries in terms of their potential to achieve sustainable happiness, by achieving sustainability at a low SWB (about 10 % of its maximum) and a high SWB (about 80 % of its maximum), respectively.