The Emperor, with the advice and approval of the Cabinet, performs those acts in matters of state, provided for in the Constitution, acting on behalf of the people. These acts include Appointing Prime Minister as designated by the Diet, Appointing Chief Justice of the Supreme Court as designated by the Cabinet, Attesting the appointment and dismissal of Ministers of State and other officials, Convoking the National Diet, Promulgating laws and treaties, Awarding honors, Attesting the credentials of ambassadors, and Receiving foreign ambassadors and ministers. Documents of Cabinet decisions pertaining to such matters of state are sent to His Majesty following each Cabinet meeting, and His Majesty looks thoroughly through these documents before signing them and affixing his seal. Furthermore, in relation to these matters of state, His Majesty attends the opening ceremony of the National Diet, and also takes part in ceremonies and events at the Imperial Palace. These ceremonies include Appointment of Prime Minister and Chief Justice of the Supreme Court, Appointment of Ministers and Officials with Imperial attestation, Receiving of Credentials of Foreign Ambassadors, and Awarding of honors.
At the Imperial Palace and the Akasaka Imperial Palace, Their Majesties host above events and various others, such as audiences, teas, lunches and dinners. Many of these events are organized to enable Their Majesties to have opportunities to offer their encouragement to people for their steady efforts in respective field, and express their appreciation to people who have accomplished outstanding achievements. These events provide opportunities for Their Majesties to meet with people from all sectors of society: People engaged in maintenance of law and order, such as National Diet members, Cabinet ministers, government officials, court judges and others; People engaged in medical and social welfare sectors such as doctors, nurses and others; Recipients of Honors and the Order of Cultural Merit; and honorees of the Japan Academy Prize and the Japan Art Academy Prize. For the purposes of nurturing international goodwill, Official State Banquets are held for visiting State Guests. Their Majesties also hold luncheons and audiences for other visiting dignitaries or foreign ambassadors to Japan. Their Majesties also meet with foreign ambassadors at the time of the arrival to take up their position in Japan and upon their departure from Japan.
Their Majesties also meet with each of the ambassadors of Japan prior to their overseas posting. Their Majesties also exchange letters and telegrams with the Heads of State of other countries.
Their Majesties make visits to various events in the Tokyo Metropolitan Area, including annual visits such as the Memorial to the Nation's War Dead, the Japan Academy Prize Ceremony, the Japan Art Academy Prize Ceremony, and the Japan Prize Ceremony.
Every year Their Majesties make four trips to regional areas to attend following events: National Arbor Day, National Sports Festival, Festival for Cherishing Sea, and National Cultural Festival. In addition to these events, Their Majesties also make visits to attend international academic meetings, and observe the local circumstances. Every year, around the Week for Persons with Disabilities, Their Majesties visit facilities for persons with disabilities. Around the time of Children’s Day and Respect for the Aged Day, Their Majesties also make visits to related welfare facilities to commemorate these special days.
Upon the invitation of foreign governments, Their Majesties make overseas visits to foster international goodwill. They have also made overseas visits to attend funeral ceremonies for members of foreign royal families.
During overseas visits, Their Majesties meet the Heads of State of the countries as well as people from variety of sectors, make visits to many facilities in various regions relating to the history, culture, industry or social welfare of the country.
Their Majesties compose waka (a classical form of poetry dating back to the 8th century Manyoshu Anthology), an age-old tradition in the Imperial Family. Their Majesties compose waka from time to time, such as on celebratory occasions. Every year in January, the ceremony of the Utakai Hajime, or the New Year’s Poetry Reading, is held at the Imperial Palace. It’s origin is said to date back to the mid-Kamakura Period. At this ceremony, ten waka that have been selected from numerous public submissions are recited in the traditional manner, together with the waka composed by Their Majesties and other members of the Imperial Family. The waka composed by Their Majesties are announced at the New Year and on other occasions.
Every year in January, Their Majesties attend the ceremony of the Kousho Hajime, or Imperial New Year’s Lectures, a tradition that dates back to 1869. Their Majesties receive lectures from preeminent scholars in the fields of human sciences, social sciences and natural sciences.
In addition, the treasures and objects that are stored at the Shosoin Repository and at the Higashiyama Collection in Kyoto, are preserved by Imperial order. The Imperial Household Agency also preserves and passes down the traditions of gagaku (Imperial court music) and various ancient equestrian traditions.
His Majesty has followed in the footsteps of His Majesty the Emperor Emeritus in honoring the tradition started by his grandfather Emperor Showa of planting and harvesting rice, which is the staple crop in Japan’s agricultural traditions. Every year, His Majesty sows rice seeds in spring, transplants the seedlings in early summer, and harvests the rice in the autumn.
Her Majesty has taken on the tradition of Imperial sericulture from Her Majesty the Empress Emerita. The Imperial sericulture was started by Empress Dowager Shoken in 1871. At the Momijiyama Imperial Cocoonery, various works for different stages of sericulture are carried out. Sericulture starts with “Hakitate”, which means brushing off newly hatched tiny silkworms from paper cards on which the eggs were laid, to baskets with fresh mulberry leaves. Then the feeding of mulberry leaves to the silkworms follows. When silkworms have achieved maturity, they are transferred into to the cocooning frames, where they spin their cocoons. The “Koishimaru” variety of silkworm is indigenous to Japan and has long been cultivated. The fine thread produced by this variety was confirmed as being the best for the restoration of silk textiles stored at the Shosoin Repository, and from 1994 until 2009 Her Majesty the Empress Emerita increased production of this variety and offered it to the Shosoin for restoration of the priceless ancient textiles. Also, in 2005 silk was also offered for the restoration of the cover and wrapping cord of the masterpiece Kasuga Gongen Genki-E (Legends of Kasuga Shrine), illustrated scrolls of the Kamakura period (Sannomaru Shozokan (Museum of the Imperial Collections)).
The cocoons and silk textiles produced at the Momijiyama Imperial Cocoonery are also used in ceremonies of the Imperial Palace and as gifts to foreign Heads of State. As well as domesticated varieties, wild varieties are also cultivated in outdoor silkworm rooms.
Since the time when they were Crown Prince and Crown Princess, Their Majesties the Emperor and Empress have honored the traditions of the Imperial Palace, including the ceremonies and rituals performed at the Three Palace Sanctuaries (Kashikodokoro, Koreiden, Shinden). Their Majesties have diligently taken on these ancient rituals and traditions that have been passed down through the ages and always pray for the happiness of the people of Japan.
Their Majesties live at the Akasaka Imperial Palace within the Akasaka Estate. In addition to official events at the Imperial Palace, Their Majesties also receive guests and hold official events at the Akasaka Imperial Palace. Their Majesties often receive lectures on academic, artistic or cultural matters, and listen to explanations from experts on the situation in Japan and overseas, on the status of post-disaster reconstruction efforts, and on various events and ceremonies. Their Majesties also host receptions at the Akasaka Imperial Palace
Their Majesties also meet with the members of the Imperial Palace volunteers, both at the Akasaka Imperial Palace, from whom they hear about the situation in the various regions of Japan and offer their encouragement.
While he was the Crown Prince, from April 1992 until March 2019, His Majesty received a commission as a visiting research fellow at the Gakushuin University Museum of History, where he continued his research on Japanese medieval history. In 2003, he gave a lecture at the Gakushuin Women's College entitled, "British Society and Culture: The Source of North American Culture," after which he gave lectures on various themes almost every year, in 2005, 2006, from 2008 to 2017, and in 2019.
With regard to water issues, in March 2003, in his capacity as Honorary President of the 3rd World Water Forum, His Majesty delivered a memorial speech at the opening ceremony of the Forum entitled, "Waterways Connecting Kyoto and Local Regions - Focusing on Ancient and Medieval Water Transport on Lake Biwa and Yodo River -". On the occasion of his visit to Mexico in March 2006, His Majesty delivered the keynote address at the opening ceremony of the 4th World Water Forum entitled, "Edo and Water Transport". In December 2007, His Majesty delivered the commemorative lecture at the opening ceremony of the 1st Asia-Pacific Water Summit, entitled "Humans and Water: From Japan to the Asia-Pacific Region". In July 2008, on the occasion of his visit to Spain, His Majesty delivered a special lecture entitled "Living with Water - Human Ingenuity and Wisdom" at the "Water Tribune" Symposium of the 2008 Zaragoza International Exposition. In March 2009, on the occasion of his visit to Turkey, His Majesty delivered a keynote speech entitled "Interacting with Water - Close Ties between Humans and Water" at the 5th World Water Forum. In March 2012, at the 6th World Water Forum held in France, a video message from His Majesty was broadcast, entitled "Water and Disaster: Learning from the History of Tsunamis" In March 2013, at the United Nations Special Thematic Session on Water and Disasters in the United States of America, His Majesty delivered a keynote address entitled "Revisiting the History of Interaction Between Human Beings and Water-related Disasters: Exploration to Find a Hint for a More Disaster-resilient Society". In April 2015, at the 7th World Water Forum in the Republic of Korea, His Majesty delivered a video message entitled “Fulfilling People`s Aspirations on Water-The Relation between Water and People through Science and Technology-”. In November 2015, at the United Nations Special Thematic Session on Water and Disasters in the United States of America, His Majesty gave a keynote lecture entitled “Quest for Better Relations Between People and Water”. In July 2017, at the United Nations Special Thematic Session on Water and Disasters in the United States of America, His Majesty sent a video message entitled “Working with Water”. In March 2018, His Majesty gave a keynote lecture titled “Water to Bring About Prosperity, Peace and Happiness” to the High Level Panel on Water and Disasters at the 8th World Water Forum in Brazil.
In addition, the fruits of His Majesty’s studies in the United Kingdom culminated in an English-language paper, "The Thames as Highway," which was published in April 1989. In September 1991 he received the honorary degree of Doctor of Law from the University of Oxford.
His Majesty is a sportsman and music lover, being an avid tennis player and also enjoying mountaineering, skiing and jogging. He is an accomplished violist.
Her Majesty is also a sports and music lover, in particular tennis and skiing.
Her Imperial Highness Princess Aiko started her third year at the Gakushuin Girl's Senior High School in April 2019.