Investiture ceremonies generally take place at Buckingham Palace, but also at Windsor Castle or the Palace of Holyroodhouse, always in a State Ball Room. These events occur about 20 times per year. Recipients get to invite only three guests to attend. (Tough decision if you have a large family, right?)
The Queen--or if the Queen is unavailable, another member of the Royal Family--enters the ball room accompanied by two Gurkha orderlies. After the national anthem is played, the ceremony begins. Each recipient's name is called, and a brief explanation of why they are being awarded is announced. The recipient then approaches the Queen, who is standing, and if the honoree is male, he bows, if female, she curtsies. The Queen gives the recipient a medal or decoration, maybe chit-chats a moment, then the recipient takes a few steps backward (while still facing the Queen) before finally turning around and heading back to his or her seat. The honoree never turns his or her back to the Queen.
The awarding of knighthood is a bit more aggrandized. Those recipients kneel before the Queen and receive an "accolade," i.e., the Queen dubs the recipient’s shoulder with a sword. (Very cool, right?)
After the awards are passed out, the national anthem is again played, then all present leave the ball room and the photo session begin. A very merry day for all! The Queen says investiture is one of her favorite duties.
There are many types of honors the queen can bestow. These are but a few of them: Knight or Dame Grand Cross of the Most Excellent Order of the British Empire (GBE), Knight or Dame Commander of the Most Excellent Order of the British Empire (KBE or DBE), Commander of the Most Excellent Order of the British Empire (CBE), Officer of the Most Excellent Oder of the British Empire (OBE), and Member of the Most Excellent Order of the British Empire (MBE)
A recent recipient of an MBE was singer Adele, for her "services to music." Prince Charles presented her award on December 19, 2013, at Buckingham Palace.
Video of an investiture (filmed in 2008)