Interior design is to create an indoor environment with reasonable function, comfort and beauty and meet people's material and spiritual needs by using material and technical means and architectural aesthetic principles according to the nature of use, environment and corresponding standards of buildings. This kind of space environment not only has the use value and meets the corresponding functional requirements, but also embodies the spiritual factors such as historical context, architectural style and environmental atmosphere.

Modern interior design is a comprehensive indoor environment design, including visual environment and engineering technology, physical environment such as sound, light and heat, psychological environment such as atmosphere and artistic conception, and cultural connotation.

Competition in interior design industry-concentration is still low and competition is fierce.

In addition to the number of enterprises, this paper also chooses the market concentration ratio (CR5) of five enterprises to measure the monopoly degree of the architectural decoration market in China, so as to observe the real changes of the market structure. By the end of 20 18, the top five enterprises in China's architectural decoration market were Jintang, Ningbo Construction Engineering Co., Ltd., Zhu Quan Co., Ltd., Guangtian Group and Yasha Co., Ltd., and their operating income in 20 18 was 24.394 billion yuan, 155438+09 million yuan and 64559 million yuan respectively. The total amount is 56610.50 billion yuan, accounting for 1.47% of the total market, which is 0.03 percentage point higher than that in 20 17 years. It can be seen that the concentration of China's architectural decoration market is constantly improving, but the degree of this improvement is not significant. Overall, the concentration of the architectural decoration market in China is still low.