Nishimura & Asahi (西村あさひ) is the largest of the "Big Four" law firms in Japan, as of January 2024, by number of lawyers.

[3] The Legal 500 ranks N&A as a top tier firm in the fields of antitrust and competition law, banking and finance, capital markets, corporate and M&A, dispute resolution, intellectural property, investment funds, labor and employment, private wealth, projects and energy, real estate and construction, restructuring and insolvency, risk management and investigations, tax, as well as technology, media, and telecommunications.

[5] N&A clients include América Móvil, Citibank, France Telecom, Fuji Fire and Marine Insurance, Johnny & Associates, KDDI, Microsoft, Mizuho Securities, Nippon Steel, NTT, Oriental Land, Tokyo Broadcasting System and Universal Studios Japan.

[6][7][8][9] Nishimura is headquartered in Tokyo (Otemachi) and has domestic branch offices in Fukuoka, Nagoya, Osaka, and Sapporo.

[10] It also has overseas offices in Bangkok, Brussels,[11] Dubai, Dusseldorf, Frankfurt, Hanoi, Ho Chi Minh City, Hong Kong, Jakarta, Kuala Lumpur, Manila, New York, Shanghai, Singapore, Taipei and Yangon.