Here's a running list of things that we think are worth booking in. It's not at all an exhaustive list, but we're hoping to highlight things that we think are special and worth seeking out. These are booking guidelines, and this information is prone to changing. Be sure to check and double check if there are things you're especially keen to do!
Sometimes if there is an attraction or gallery you're really hoping to get to, but you've missed out on booking directly, you'll be able to buy tickets through a third party, or ticket reseller. This isn't great- but if it's worth it to you, wear the extra cost.
Some of these places require phone bookings, you may wish to use a concierge service.
Hotels and Accommodation
Kyoto
Len Hostel: Four months in advance.
Book at: https://backpackersjapan.co.jp/kyotohostel/booking/
Read more about Len
Tokyo
Claska: Six months in advance.
Book at: http://www.claska.com/en/hotel/index.html
Osaka
Eating and Drinking
Kyoto
AWOMB: Nishikiya Town, reservations accepted for lunch.
AWOMB: Karasuma, reservations accepted for lunch only.
Two months in advance, by phone only. No children under six.
http://www.awomb.com/
Tokyo
Den: Two months in advance, by phone only. No third-party services. https://www.jimbochoden.com/en/reserve/
Osaka
Exhibitions, Galleries and Museums
Tokyo
Mori Digital Art Museum: Team Borderless: https://ticket.teamlab.art/
Tickets seem to be on release about a month in advance, and are selling out.
Naoshima
Chichu Art Museum: Two months in advance, recommend booking on release day.
http://www.e-tix.jp/chichu/en/
James Turrell 'Open Sky' Night Program (at Chichu Museum, must also have museum tickets): Three months in advance
http://benesse-artsite.jp/en/art/chichu.html