IPM (integrated pest management) is:
Set Action Thresholds
Monitor and Identify Pests
Prevention
Control
IPM is not a single pest control method but, rather, a series of pest management evaluations, decisions and controls. In practicing IPM, growers who are aware of the potential for pest infestation follow a four-tiered approach. The four steps include:
Before taking any pest control action, IPM first sets an action threshold, a point at which pest populations or environmental conditions indicate that pest control action must be taken. Sighting a single pest does not always mean control is needed. The level at which pests will either become an economic threat is critical to guide future pest control decisions.
Not all insects, weeds, and other living organisms require control. Many organisms are innocuous, and some are even beneficial. IPM programs work to monitor for pests and identify them accurately, so that appropriate control decisions can be made in conjunction with action thresholds. This monitoring and identification removes the possibility that pesticides will be used when they are not really needed or that the wrong kind of pesticide will be used.
As a first line of pest control, IPM programs work to manage the crop, lawn, or indoor space to prevent pests from becoming a threat. In an agricultural crop, this may mean using cultural methods, such as rotating between different crops, selecting pest-resistant varieties, and planting pest-free rootstock. These control methods can be very effective and cost-efficient and present little to no risk to people or the environment.
Once monitoring, identification, and action thresholds indicate that pest control is required, and preventive methods are no longer effective or available, IPM programs then evaluate the proper control method both for effectiveness and risk. Effective, less risky pest controls are chosen first, including highly targeted chemicals, such as pheromones to disrupt pest mating, or mechanical control, such as trapping or weeding. If further monitoring, identifications and action thresholds indicate that less risky controls are not working, then additional pest control methods would be employed, such as targeted spraying of pesticides. Broadcast spraying of non-specific pesticides is a last resort. In organic gardening, like our garden, only natural organic methods are used in place of synthetic pesticides.
(info from EPA)
Here is what I found around the garden today:
Here is a picture of crucifer flea beetles on my Toscano Kale, and the damage they do. A severe infestation looks like a leaf was shot with hundreds of BB's. It is ugly, but for the most part, plants can recover. It can do major damage to new seedlings and small plants though. They can defoliate a young plant so fast that it no longer has any leaf tissue left to photosynthesize, so the plant dies. Once the plant is established, it seems to tolerate it better. Flea beetles especially like hot, dry soil. You can try to put row covers down, but I find that they sneak their way underneath anyways. Their larvae also overwinter in the soil, so there is a chance that they are hatching and being trapped underneath anyways. You can also net the plant with nylon or tulle and tie it at the bottom to try and save it.
Here is a well-fed Cabbage Looper. Hard to spot, but the damage is not! This one looks like it was starting to spin a cocoon on my Cauliflower leaf. Development from egg to adult can be completed in about 35 days. Four generations or more can be produced each year. If you see white moths flying around your garden, you can probably find these on your plants. The best way to avoid them is to put row covers over your seedlings the day you set them out. I am never that organized, so I have obviously missed that window. Handpicking is usually not sufficient, as they seem to take over the plants rather fast. They also cover them with excrement, which is how I noticed this one. Bt is your best bet for control. 
Here is a small Cabbage Looper that probably just hatched.
Here is a Three-Lined Potato Beetle that I found on Tom's potatoes. Similar to flea beetles, the main problem with these is defoliation. They are also pretty disgusting insects.
Here are some beet leaves with leaf miner damage. These are rarely a problem to the actual beet, but some people like to eat the greens as well, and finding a worm tunneling in between the two layers of a leaf is not the most appetizing thing. They also affect Spinach, Swiss Chard, and a few other plants.
With the cucumbers, squash and zucchini just starting to come up now, I'm sure we will have another post on insects very soon. Anyone seen any Cicadas? :)
(for those of you who are new to blogs, the blue underlined words mean you can click on them for more information. I have previously written "click for more info", but will now just highlight the word that I am linking.)
