I'll write more about this in the future. Below is my taxonomy for approaches to development. Each includes an example of an effective practitioner who takes (primarily) that approach. There are plenty of hybrids, so I'll list some of my favorite examples of those.
All the names are a little mocking and irreverent because I think setting a tone of being both unserious and critical is important. Too many people are critical (which is important), but dead serious and rigidly ideological, when talking about different approaches to doing a project.
1. The Beggar (Lobbyist)
The beggar lobbies governments for money and legislation. For example, the Live8 concerts, organized by Bob Geldof, lobbied the G8 countries to commit to doubling funding for foreign aid. The NGO ONE in the United States, and its celebrity spokesman Bono, lobby for legislation on debt relief (Jubilee Act), cutting farm subsidies (FRESH amendment), trade reform (GROWTH Act), and providing funding for the treatment of AIDS (PEPFAR).
Examples: Bono and Bob Geldof, ONE Campaign
The appeal of the beggar is plain enough: governments have a lot of money and can use it to solve social problems. We spend a lot of time campaigning for our political parties in the US because we believe their approach to health care or education will improve our systems here. Since many problems in the developing world are likewise problems of education and health care, doesn't the same approach makes sense?
The main criticism of the beggar is that he or she usually doesn't understand the complexity of the issues. Lobbying for bad policy can hurt on a massive scale the same way lobbying for good policy can help on on a huge scale. Also, many intellectuals in the countries receiving the aid the beggar lobbies for think that the aid is paternalistic and encouraging laziness and outright corruption in the receiving country.
2. The Policy Entrepreneur (Academic)
The policy entrepreneur is usually a professor or other academic working for a think tank. They argue for policy reforms based on their research. Esther Duflo, co-founder of the Poverty Action Lab at MIT, is a prime example of an effective policy entrepreneur. Her and her colleague's research has shown which interventions in education, water infrastructure, health and microfinance have the biggest impact. Based on that evidence they have worked to reform policy in both the developed world (foreign aid policy) and the developing world (domestic policy).
Examples: Esther Duflo and co., Santiago Levy and Jose Gomez de Leon, Michael Clemens
The appeal of the policy entrepreneur is straight forward: policy decisions have a much bigger impact than small projects, so making good policy decisions should do more good than doing good small projects. The problem is this can work in reverse. Some policy entrepreneurs turn out to be wrong about issues in the long run and thus each runs the risk of making policy worse, not better. Also, many policy entrepreneurs never have much impact on policy.
Hybrid: Jeff Sachs is both a grade A beggar and policy entrepeneur
3. The Mad Scientist (Inventor)
The mad scientist is focused on technology. There are a lot of mad scientists at engineering colleges such as MIT and in universities with Engineers without Borders chapters. The mad scientist thinks primarily on a small scale, hoping to invent neat new technologies that solve basic problems at low cost. Many of these technologies are directed at income generation, but some are also useful for improving health (e.g. delivering vaccines more effectively).
Examples: Amy Smith
The biggest problem for the mad scientist is that their technologies rarely reach the field after endless prototyping. Economists also often question the utility of this approach by noting that all the technology needed for development already exists and arguing that the problem is how the resources are utilized and distributed.
4. The Dentist (Behavior Change)
The dentist focuses on behavior change. In many cases people in the developing world have poor health or education outcomes because they don't make much effort in school or practice basic sanitation practices. The work of the dentist is difficult--like pulling teeth--hence the name. Particular examples of dentistry are total community-led sanitation, which encourages villagers in rural Asia, to take responsibility for their community's sanitation; hand-washing programs world-wide which encourage people to wash their hands; similar problems encourage the use of condoms and boiling water before drinking it.
Examples: TCLS, Public-Private Partnership for Handwashing with Soap
The main complaints about dentistry are that the dentists are trying to tell people what to do with their lives and that their projects tend to be very slow moving, with only incremental successes. The later tends to be valid while the former is not necessarily a fair representation of dentistry, see TCLS.
Hybrid: Paul Polack of IDE is a Dentist mixed with a Mad Scientist. His organization develops technologies for use by rural farmers, but spends at least as much time convincing farmers to take a risk and buy them.
5. The Santa Claus (Charity)
The Santa Claus has the most basic approach: hand out gifts. This approach is almost too simple to comment on, so I'll just throw in that it's my favorite. The Measles Initiative, which vaccinated millions of kids against measles (and other diseases); Partners in Health, which provides free medical care; and Nothing But Nets, which hands out bed-nets, are three of my favorite development projects.
Examples: Paul Farmer
The Santa Claus, while often the most effective development practitioner, and in rare cases the most celebrated (Paul Farmer), is far and away the most criticized. The Santa Claus is accused to eliminating intrinsic motivation, creating learned helplessness and a culture of dependency, and in general being ineffective as resources are (according to one theory) better allocated using the price system. For people who see development as capacity-building the Santa Claus is repulsive for ideological reasons, whereas pragmatists focused on improving health and quality of life, tend to appreciate some aspects of the Santa Claus approach.
Hybrid: Nearly every development practitioner plays the Santa Claus from time to time, often without noticing it.
6. The Petty Bourgeois (Small Business)
The petty bourgeois are businesspeople who espouse the virtues of microfinance and other private sector (but small scale) interventions. They tend to like projects that start restaurants, small service businesses or cottage industry manufacturing.
Examples: Jacqueline Novogratz, Iqbal Quadir
The main criticisms leveled at the petty bourgeois is that they aim too low. If you help someone making $500 a year to make $550 how much good does that do? What does that person spend the money on? Booze, parties or education? Economists have pointed out that because the poor tend to have little human capital and can only acquire small amounts of physical capital with small loans, they will never be able to earn large profits. Economists have also noted that many people who extend microcredit to the poor have enabled the poor to get deep into debt without necessarily raising their income, which might be a bad thing.