The Bank of Canada (or simply BoC) (French: Banque du Canada) is Canada's central bank. The bank was chartered by and under the Bank of Canada Act on July 3, 1934, as a privately owned corporation. In 1938, the bank was legally designated a federal Crown corporation. The Minister of Finance holds the entire share capital issued by the bank. "The capital shall be divided into one hundred thousand shares of the par value of fifty dollars each, which shall be issued to the Minister to be held by the Minister on behalf of Her Majesty in right of Canada."
The essential role of the bank, as Canada's central bank, is to "promote the economic and financial well-being of Canada."
This role follows from the purpose of the Bank as set out in the preamble to the Bank of Canada Act: "to regulate credit and currency in the best interests of the economic life of the nation, to control and protect the external value of the national monetary unit and to mitigate by its influence fluctuations in the general level of production, trade, prices and employment, so far as may be possible within the scope of monetary action, and generally to promote the economic and financial welfare of Canada". 
With the exception of the word "Canada" replacing the word "Dominion" the wording today is identical to the 1934 legislation which created the bank.  Changes to make the bank a government-owned institution in 1938 did not alter the purpose of the Bank as set out in the preamble to the Bank of Canada Act.
More specifically, the responsibilities of the bank are:
The Bank of Canada headquarters are located at the Bank of Canada Building, 234 Wellington Street in the nation's capital, Ottawa. The edifice also houses the Currency Museum, which opened in December, 1980.
Between 2013 and early 2017, the Bank of Canada temporarily moved its offices to 234 Laurier Street in Ottawa to allow major renovations to its headquarters building.
On March 11, 1935, the Bank of Canada began operations, following the granting of Royal Assent to the Bank of Canada Act. Initially, the bank had been founded as a privately owned corporation, a move taken in order to ensure the bank would be free from partisan political influence. Earlier, in 1933, Prime Minister R.B. Bennett had instituted the Royal Commission on Banking and Currency and it reported its policy recommendations in favour of the establishment of a central bank for Canada. The Royal Commission's members had consisted of noted Scottish jurist Lord Macmillan, Bank of England director Sir Charles Addis, former Canadian Finance Minister William Thomas White, Banque Canadienne de Montreal general manager Beaudry Leman, and Premier of Alberta John Edward Brownlee.. In 1938, under Prime Minister William Lyon Mackenzie King, the Bank of Canada, by Act of the Parliament of Canada became "a special type of " Crown corporation.
"The Bank shall be under the management of a Board of Directors composed of a Governor, a Deputy Governor and twelve directors appointed in accordance with this Act. ... The Governor and Deputy Governor shall be appointed by the directors with the approval of the Governor in Council." "Before a person starts to act as a director, an officer or an employee of the Bank, he or she shall take an oath, or make a solemn affirmation, of fidelity and secrecy, in the form set out in the schedule, before a commissioner for taking affidavits."
Prior to the creation of the Bank of Canada, the federal Department of Finance had been responsible for printing Canada's banknotes. The Bank of Montreal, then the nation's largest bank, acted as the government's banker. In 1944, the Bank of Canada then became the sole issuer of legal tender banknotes in and under Canada.
After the war, the bank's role was expanded as it was mandated to encourage economic growth in Canada. An Act of Parliament in September 1944 established the subsidiary Business Development Bank of Canada (BDC) to stimulate investment in Canadian businesses. Prime Minister John Diefenbaker's central-bank monetary policy was directed towards increasing the money supply to generate low interest rates, and incentivize full employment. When inflation began to rise in the early 1960s, then-Governor James Coyne ordered a reduction in the Canadian money supply.
Since the 1980s, the main priority of the Bank of Canada has been keeping inflation low. As part of that strategy, interest rates were kept at a low level for almost seven years. Since September 2010, the key interest rate (overnight rate) was 0.5%. In mid 2017, inflation remained below the Bank's 2% target, (at 1.6%), mostly because of reductions in the cost of energy, food and automobiles; as well, the economy was in a continuing spurt with a predicted GDP growth of 2.8 percent by year end. Early on 12 July 2017, the bank issued a statement that the benchmark rate would be increased to 0.75%. "The economy can handle very well this move we have today and of course you need to preface that with an acknowledgment that of course interest rates are still very low," Governor Stephen Poloz subsequently said. In its press release, the bank had confirmed that the rate would continue to be evaluated at least partly on the basis of inflation. "Future adjustments to the target for the overnight rate will be guided by incoming data as they inform the bank's inflation outlook, keeping in mind continued uncertainty and financial system vulnerabilities." Poloz refused to speculate on the future of the economy but said, "I don't doubt that interest rates will move higher, but there's no predetermined path in mind at this stage".
The mandate of the Bank of Canada is defined in the Bank of Canada Act preamble and it states,
WHEREAS it is desirable to establish a central bank in Canada to regulate credit and currency in the best interests of the economic life of the nation, to control and protect the external value of the national monetary unit and to mitigate by its influence fluctuations in the general level of production, trade, prices and employment, so far as may be possible within the scope of monetary action, and generally to promote the economic and financial welfare of Canada.
The bank's current mission statement is: The Bank of Canada's responsibilities focus on the goals of low, stable and predictable inflation; a safe and secure currency; a stable and efficient financial system in Canada and internationally; and effective and efficient funds-management services for the Government of Canada, as well as on its own behalf and for other clients.
In practice, however, it has a more narrow and specific internal definition of that mandate: to keep the rate of inflation (as measured by the Consumer Price Index) between 1% and 3%. Since adoption of the 1% to 3% inflation target in 1991  and 2015, the average inflation rate was 1.79% . . The most potent tool the Bank of Canada has to achieve this goal is its ability to set the interest rate for borrowed money.
Canada no longer requires banks to maintain fractional reserves with the Bank of Canada. Instead, banks are required to hold highly liquid assets such as treasury bills equal to 30 days of normal withdrawals (liquidity coverage), while leverage is primarily tied to adequate loss-absorbing capital, notably tier one (equity) capital. 
The Bank of Canada is structured as a Crown corporation rather than as a government department, with shares held in the name of the Minister of Finance on behalf of the government. While the Bank of Canada Act provides the Minister of Finance with the final authority on matters of monetary policy through the power to issue a directive" no such directive has ever been issued. The bank's earnings go into the federal treasury. The governor and senior deputy governor are appointed by the bank's board of directors. The Deputy Minister of Finance sits on the board of directors but does not have a vote. The bank submits its spending to the board of directors, while departmental spending is overseen by the Treasury Board with their spending estimates submitted to Parliament. Its employees are regulated by the bank and not the federal public service agencies.
The bank has a zero book value policy on its balance sheet—matching total assets to total liabilities—and transfers any equity above this amount as a dividend to the Government of Canada. As of December 30, 2015 the Bank of Canada owned C$95 billion in Government of Canada debt. It had a net income in 2014 of $1.039 billion. The Bank of Canada matches its liabilities of $76 billion in currency outstanding, $23 billion in deposits from the government and $3.5 billion in other liabilities—to its assets owning $95 billion in Government of Canada debt and $7.5 billion in other assets. Bank notes in circulation have increased from $70 billion at the end of 2014 to $76 billion at the end of 2015. The Bank of Canada lists cash on its 2014 balance sheet at $8.4 million in currency and foreign deposits. The Bank of Canada's books are audited by external auditors who are appointed by Cabinet on the recommendation of the Minister of Finance, and not by the Auditor General of Canada.
The Bank of Canada 2008 balance sheet expanded to $78.3 billion from $53.7 billion from the previous year. After the financial crisis, these emergency asset purchases were unwound and removed from the central bank's balance sheet. This action represented a fifty percent increase in the size of the central bank's balance sheet. This central bank transaction was referenced under "securities purchased for resale" from Canada's major banks. It was termed advances to members of the Canadian Payments Association and were liquidity loans made under the bank’s standing liquidity facility as well as term advances made under the bank’s commitment to provide term liquidity to the Canadian financial system.
In December 2015, the Bank of Canada forecasted increasing annual growth throughout 2016 and 2017, with the Canadian economy reaching full capacity mid-2017. With this annual growth, the Bank estimated the effective lower bound for its policy interest rate to hit approximately 0.5 per cent. This is differing from the Bank’s 2009 assessment of 0.25 per cent. 
To ensure Canada’s monetary system remains intact should another financial crisis take place, for example the 2007-2008 global financial crises, the Bank of Canada has put forward a framework for the use of unconventional monetary policy measures.
Principles surrounding the use of unconventional policies have not changed since 2009. Although each crisis is unique, the Bank will ensure it attains its primary focus of achieving the inflation rate.
The Bank of Canada has established these unconventional monetary policy measures after reflecting on its previous annex in its April 2009 MPR, as well as how other central banks responded to the global financial crisis. These measures are in place so, in the improbable circumstance the economy is hit with another significant negative financial shock, the Bank of Canada has principles it can reference. These measures are strictly hypothetical and are in no means being embarked upon at any foreseeable date. The unconventional monetary policy measures is also a living document; because the post-crisis adjustment process continues to develop and best practices are still being garnered, these measures will continue to be worked on and altered as needed. 
The framework for the use of unconventional monetary policy measures includes the following four tools:
The first option within the Bank of Canada’s toolkit for its framework for the use of unconventional monetary policy measures is forward guidance as it relates to substantial impacts for the future. An example of forward guidance would be the Bank’s 2009 statements regarding the conditional commitment to keeping the key policy rate untouched for a year, so long as the inflation rate remained unaffected during this time. Forward guidance, when partnered with conditional commitments, is both an effective and credible approach, allowing the Bank to deliver on its commitment as long as the condition in question is upheld.
Large-scale asset purchases
Although the Bank of Canada engages in asset purchases regularly as for its balance sheets to grow with the economy and enable the distribution of a growing stock of bank notes, in this circumstance, it would go beyond even that to participate in large-scale asset purchases.
Often referred to as quantitative easing, large-scale asset purchases involve establishing new reserves for the purpose of purchasing large quantities of securities, for example government bonds or private assets, such as mortgage-backed securities, from the private sector. The benefits to these purchases are three-fold:
Funding for credit
The third unconventional monetary policy tool is funding for credit, which ensures economically-important sectors continue to have access to funding, even if the supply of credit is impaired. In order for this to be effective, the Bank of Canada would provide collateralized funding to others at a subsidized rate as long as they met specified lending objectives. This tool is designed to encourage lending to households and businesses when banks may otherwise face increasing funding costs.
Negative interest rates
Pushing for short-term interest rates below zero has become common amongst many banks, including ECB and Swiss National Bank. Due to the negative interest rates, these financial markets have adapted when faced with a financial crisis and continue to function. The Bank of Canada believes the Canadian financial market is capable of functioning in a negative interest rate environment and, as such, added it to its toolkit for unconventional monetary policy measures.
In previous years, the Bank of Canada had a predetermined sequence of measures in place should a crisis take place. These newly created unconventional measures will work towards finding a solution to a problem in whichever combination of policies is judged appropriate at the given time under their unique circumstances. These unconventional measures, and the sequence in which they would be adapted, are designed to minimize market distortions, as well as risk to the Bank of Canada’s balance sheet.
The head of the Bank of Canada is the governor. While the law provides the Board of Directors with the power to appoint the Governor, in practice they approve the choice of the government. The governor serves a fixed seven-year term which may be renewed, but recent governors have only chosen to serve a single term. With the exception of matters of personal conduct ("good behavior") the Bank of Canada Act does not provide the government with the direct ability to remove a governor during his or her term in office. In the case of a profound disagreement between the government and the Bank, the Minister of Finance can issue written instructions for the bank to change its policies. This has never actually happened in the history of the bank to date. In practice, the Governor sets monetary policy independently of the government.
Canadian banknotes bear the signature of the governor and deputy governor of the Bank of Canada.
The Bank of Canada has a large economic research staff which prepare reports independently from the Bank’s Governing Council. This research may support the prevailing policy views of the Governing Council, but may also differ from official Bank views with the opinions expressed being those solely of the authors.
The analytical notes, discussion papers and working papers prepared by the Bank's economic staff are published on the Bank's website and in its online monthly Research Newsletter, several are published in the quarterly Bank of Canada Review.
The Bank of Canada has a team of chemists, physicists, and engineers it had assembled for the development of the Canadian Journey Series who determine potential counterfeiting threats and assess substrate materials and potential security features for use in banknote designs. It is part of the "Four Nations Group" of central banks, which includes the Reserve Bank of Australia, the Bank of England, and the Bank of Mexico, that collaborate on banknote security research, testing, and development.