1.Audit and Other assurance services 2.statutory audits
What are Assurance Services 
An assurance engagement is an engagement in which a practitioner expresses a conclusion designed to enhance the degree of confidence of the intended users other than the responsible party about the outcome of the evaluation or measurement of a subject matter against criteria.
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Assurance engagements are generally voluntary but may be a requirement imposed on the entity by another party.
What are Assurance Services
Assurance is opinion expressed by an assurance provider on a subject matter. It is important because it enhances the degree of confidence place in the subject matter by the intended users as to the evaluation or measurement against suitable criteria.
Features of an assurance engagement are:
Subject matter
The three main parties involved:
Responsible person
Assurance provider (practitioner)
Intended user
The report
What are Assurance Services
Examples of assurance engagements include:
Annual external audit of financial statements (‘statutory’ assurance/audit)
Half-year review of results
Going concern review
Review of effectiveness of an entity's IT system
Review of compliance with corporate governance requirements
An assurance report provides the following benefits to the users of financial information:
Independent opinion from an external source that enhances the credibility of the information
Management bias is reduced
Modified opinion draws attention to risk
The relevance of the information may be improved by the expertise and knowledge of the assurance firm.
What are Assurance Services
All assurance engagements, whether subjected to legal regulation such as statutory audit or a contractual arrangement should be performed in a similar manner:
Agree the scope of work to be performed
Formalize all of the terms of the engagement in a contract (engagement letter)
Plan the work. The level of work should be based on the risk and level of assurance desired
Obtain sufficient appropriate evidence on which to base the conclusion
Perform overall review and form opinion
Issue report to the client.
Levels of Assurance in Report 
Two levels of assurance can be provided by a practitioner depending on the nature of engagement:  Reasonable
assurance engagement in which Positive Assurance is given.
 Moderate
or Limited assurance engagement in which Negative Assurance is given.
Levels of Assurance in Report Positive Assurance 
Positive assurance is where a lot of detail work has been carried out on a subject matter and therefore the assurance provider can conclude confidently, in their opinion, that the subject matter has been either properly prepared or not. Positive assurance is a high level of assurance and therefore a high level of reliance can be placed upon it.
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Positive assurance does not mean that the subject matter has been prepared well it just means that we the auditors can positively say that we did sufficient work and found that the subject matter is either good or bad.
Levels of Assurance in Report Negative Assurance 
Negative assurance is where a smaller amount of work has been carried out on a subject matter and no errors were discovered, there may be errors or inaccuracies but none were discovered with the level of work. This is a much lower level of assurance and therefore less reliance should be placed on negative assurance.
Statutory Audits
Statutory audits are a legal requirement. This is where a team of auditors independent of the company check the Financial Statements on behalf of the shareholders as to the Truth and Fairness of the figures reported, as well as, if they were prepared in accordance with the relevant accounting standards and legal framework.
The auditing profession is subject to regulation from a range of sources.
National legislation
National regulation and standard-setting
International standard-setting
Professional bodies, eg ICMAP
Statutory Audits
The objective of statutory audit is to issue an opinion in line with statutory requirements.
In more general terms, the objective could be described as 'providing assurance to the users of financial statements'.
There are two key aspects to the opinion, that must be explicitly reported:
Whether a true and fair view is given by the financial statements
Whether the financial statements have been properly prepared in accordance with relevant legal requirements.
Other regulations, such as local law and corporate governance codes, may require the auditor to consider other aspects and report on them either positively or by exception.