Principles

The underlying principles, called "The Toyota Way" are outlined as follows:

Long-term philosophy
Main article: The Toyota Way
Base your management decisions on a long-term philosophy, even at the expense of short-term financial goals.

The right process will produce the right results
Create continuous process flow to bring problems to the surface
Use the "pull" system to avoid overproduction
Level out the workload (heijunka). (Work like the tortoise, not the hare.)
Build a culture of stopping to fix problems, to get quality right from the first
Standardized tasks are the foundation for continuous improvement and employee empowerment
Use visual control so no problems are hidden
Use only reliable, thoroughly tested technology that serves your people and processes.

Add value to the organization by developing your people and partners
Grow leaders who thoroughly understand the work, live the philosophy, and teach it to others.
Develop exceptional people and teams who follow your company's philosophy.
Respect your extended network of partners and suppliers by challenging them and helping them improve.

Continuously solving root problems drives organizational learning
Go and see for yourself to thoroughly understand the situation (Genchi Genbutsu, 現地現物);
Make decisions slowly by consensus, thoroughly considering all options (Nemawashi, 根回し); implement decisions rapidly;
Become a learning organization through relentless reflection (Hansei, 反省) and continuous improvement (Kaizen, 改善).

The Toyota production system has been compared to squeezing water from a dry towel. What this means is that it is a system for thorough waste elimination. Here, waste refers to anything which does not advance the process, everything that does not increase added value. Many people settle for eliminating the waste that everyone recognizes as waste. But much remains that simply has not yet been recognized as waste or that people are willing to tolerate.

People had resigned themselves to certain problems, had become hostage to routine and abandoned the practice of problem-solving. This going back to basics, exposing the real significance of problems and then making fundamental improvements, can be witnessed throughout the Toyota Production System.

Results
Toyota was able to greatly reduce leadtime and cost using the TPS, while improving quality. This enabled it to become one of the ten largest companies in the world. It is currently as profitable as all the other car companies combined and became the largest car manufacturer in 2007. It has been proposed that the TPS is the most prominent example of the 'correlation', or middle, stage in a science, with material requirements planning and other data gathering systems representing the 'classification' or first stage. A science in this stage can see correlations between events and can propose some procedures that allow some predictions of the future. Due to the success of the production philosophy's predictions many of these methods have been copied by other manufacturing companies, although mostly unsuccessfully.

Commonly used terminology
Andon (行灯) (English: Signboard)
Genchi Genbutsu (現地現物) (English: Go and see for yourself)
Hansei (反省) (English: Self-reflection)
Heijunka (平準化) (English: Production Smoothing)
Jidoka (自働化) (English: Autonomation - automation with human intelligence)
Just In Time (ジャストインタイム) (JIT)
Kaizen (改善) (English: Continuous Improvement)
Kanban (看板, also かんばん) (English: Sign, Index Card)
Manufacturing supermarket where all components are available to be withdrawn by a process
Muda (無駄, also ムダ) (English: Waste)
Mura (斑 or ムラ) (English: Unevenness)
Muri (無理) (English: Overburden)
Nemawashi (根回し) (English: Laying the groundwork, literally: Going around the roots)
Poka-yoke (ポカヨケ) (English: fail-safing - to avoid (yokeru) inadvertent errors (poka))