Technology is not a panacea. However, it can be extremely useful in solving many kinds of problems. Improved housing and plumbing will increase health. More efficient agriculture and industry save water, land, materials, and labor, and reduce pollution. Access to information, education, and communication provides many opportunities for self improvement, economic efficiency, and participatory government. Cheap, reliable power is vital for the use of other technologies and provides many conveniences. Today, technology relies on distributed manufacturing, which requires many specialized materials and machines and highly trained labor. It is a difficult and slow process to develop an adequate technology base in an impoverished area. However, molecular manufacturing does not require skilled labor or a large supporting infrastructure; a single personal nanofactory (PN) with a single chemical supply and power supply can produce a wide range of useful, reliable products, including copies of itself to double the manufacturing infrastructure in hours, if desired. Thus PNs, and many of their products, are "appropriate technology" for almost any setting.

A few basic problems create vast amounts of suffering and tragedy. According to a World Bank document, water is a major concern of the U.N. Almost half the world's population lacks access to basic sanitation, and almost 1.5 billion have no access to clean water. Of the water used in the world, 67% is used for agriculture, and another 19% for industry. Residential use accounts for less than 9%. Much industry can be directly replaced by molecular manufacturing. Agriculture can be moved into greenhouses. Residential water can be treated and recycled. Adoption of these steps could reduce water consumption by at least 50%, and probably 90%. Water-related diseases kill thousands, perhaps tens of thousands, of children each day. This is entirely preventable with basic technology, cheap to manufacture—if the factories are cheap and portable. MNT can provide similar opportunities in many other areas.

Much water today is wasted because it is almost but not entirely pure. Simple, reliable mechanical and electrical treatment technologies can recover brackish or tainted water for agricultural or even domestic use. These technologies require only initial manufacturing and a modest power supply. Physical filters with nanometer-scale pores can remove 100% of bacteria, viruses, and even prions. An electrical separation technology that attracts ions to supercapacitor plates can remove salts and heavy metals. The ability to recycle water from any source for any use can save huge amounts of water, and allow the use of presently unusable water resources. It can also eliminate downstream pollution; a completely effective water filter also permits the generation of quite "dirty" waste streams from agricultural and industrial operations. As long as the waste is contained, it can be filtered, concentrated, and perhaps even purified and used profitably. As with anything built by molecular nanotechnology, initial manufacturing costs for a water treatment system would be extremely low. Power will be cheap (see below). Well-structured filter materials and smaller actuators will allow even the smallest filter elements to be self-monitoring and self-cleaning. Self-contained, small, completely automated filter units can be integrated in systems scalable over a wide range.

Moving agriculture into greenhouses can recover most of the water used, by dehumidifying the exhaust air and treating and re-using runoff. Additionally, greenhouse agriculture requires less labor and far less land area than open-field agriculture, and provides greater independence from weather conditions including seasonal variations and droughts. Greenhouses, with or without thermal insulation, would be extremely cheap to build with nanotechnology. A large-scale move to greenhouse agriculture would reduce water use, land use, and weather-related food shortages.

The main source of power today is the burning of carbon-containing fuels. This is generally inefficient, frequently non-renewable, and dumps carbon dioxide and other waste products (including radioactive substances from coal) into the atmosphere. Solar energy would be feasible in most areas of the globe if manufacturing and land were sufficiently cheap and energy storage were sufficiently effective. Solar electricity generation depends on either photovoltaic conversion, or concentrating direct sunlight. The former works, although with reduced efficiency, on cloudy days; the latter can be accomplished without semiconductors. In either case, not much material is required, and mechanical designs can be made simple and fairly easy to maintain. Sun-tracking designs can benefit from cheap computers and compact actuators. Energy can be stored efficiently for several days in relatively large flywheels built of thin diamond and weighted with water. Smaller energy storage systems can be built with diamond springs, providing a power density similar to chemical fuel storage and much higher than today's batteries. Water electrolysis and recombination provide scalable, storable, transportable energy. However, there is some cost in efficiency and in complexity of technology to deal safely with large-scale hydrogen storage or transportation.

Solar solutions can be implemented on an individual, village, or national scale. The energy of direct sunlight is approximately 1 kW per square meter. Dividing that by 10 to account for nighttime, cloudy days, and system inefficiencies, present-day American power demands (about 10 kW per person) would require about 100 square meters of collector surface per person. Multiplying this figure by a population of 325 million (estimated by the US Census Bureau for 2020) yields a requirement for approximately 12,500 square miles of area to be covered with solar collectors. This represents 0.35% of total US land surface area. Much of this could be implemented on rooftops, and conceivably even on road surfaces.

A person's living space has a significant effect on their quality of life. The ability to exclude insects will greatly reduce certain diseases. Thermal insulation can increase comfort and often reduce energy consumption. Water and sewage piping and fixtures increase sanitation and decrease disease. House styles are as varied as cultures, and living spaces cannot and should not be standardized worldwide. However, building supplies and home systems (e.g. power, plumbing) require less diversity, and useful components may be built from predesigned plans. In many areas of the world, something as simple as a water filter or a mosquito net can save many lives. Such small, simple products would cost almost nothing to produce. In areas that already use rectilinear apartment construction, including most inner cities, double-layer, vacuum-insulated wall panels can greatly decrease noise transmission between adjacent living spaces as well as providing excellent thermal insulation. Living space reform cannot be approached as a single problem with an easy solution, but the worst problems can easily be addressed piecemeal.

Molecular manufacturing can create computer logic gates a few nanometers on a side, and efficient enough to be stacked in 3D. An entire supercomputer can fit into a cubic millimeter, and cost a small fraction of a cent. With actuators smaller than a bacterium, a thin, high-resolution computer display will be easy (and cheap) to build. With GHz mechanical frequencies, a mostly-mechanical device can sense and produce radio waves. Thus computation, communication, and display are all feasible with pure diamondoid technology. Computers, PDAs, and cell phones can be cheap enough for even the poorest people on earth to own one, and contain more than enough processing capability for a voice interface for illiterate people. Distributed networking hardware can likewise be very cheap, and distributed networking software, though not trivial, is already being developed. The whole world could get "wired" within a year.

Environmental degradation is a serious problem with many sources and causes. One of the biggest causes is farming. Greenhouses can greatly reduce water use, land use, runoff, and topsoil loss. Mining is another serious problem. When most structure and function can be built out of carbon and hydrogen, there will be far less use for minerals, and mining operations can be mostly shut down. Manufacturing technologies that pollute can also be scaled back. In general, improved technology allows operations that pollute to be more compact and contained, and cheap manufacturing allows improvements to be deployed rapidly at low cost. Storable solar energy will reduce ash, soot, hydrocarbon, NOx, and CO2 emissions, as well as oil spills. In most cases, there will be strong economic incentives to adopt newer, more efficient technologies as rapidly as possible. Even in areas that currently do not have a technological infrastructure, self-contained molecular manufacturing will allow the rapid deployment of environment-friendly technology.

Molecular manufacturing will impact the practice of medicine in many ways. Medicine is highly complex, so it will take some time for the full benefits to be achieved, but many benefits will occur almost immediately. The tools of medicine will become cheaper and more powerful. Research and diagnosis will be far more efficient, allowing rapid response to new diseases, including engineered diseases. Small, cheap, numerous sensors, computers, and other implantable devices may allow continuous health monitoring and semi-automated treatment. Several new kinds of treatment will become possible. As the practice of medicine becomes cheaper and less uncertain, it can become available to more people.

Much social unrest can be traced directly to material poverty, ill health, and ignorance. Molecular manufacturing can eliminate material poverty—at least by today's standards; post-MM standards may be considerably higher. Products of molecular manufacturing can greatly improve health by eliminating conditions that cause disease, including poor sanitation, insects, and malnutrition. Widespread availability of computers and communication devices can provide exposure to other cultures and diverse points of view, and create an understanding of a broader social context in which to evaluate actions and beliefs. (Unfortunately, mass communication also gives demagogues a wider audience, which may undo some of this benefit.)  MM certainly will not cure or prevent social unrest, but it will remove many tangible causes of distress.