OECD Style Guide (Fourth Edition)

11. Punctuation

Abstract

Punctuation marks clarify meaning and indicate pauses, stops or shifts in tone. They help to separate ideas, signal emphasis and convey relationships between parts of a text.

General rules

• Be consistent in the punctuation used throughout the text.

• Use punctuation thoughtfully, without excessive repetition of marks that may confuse the reader.

• Match punctuation to tone and style; some marks may be more appropriate in informal writing than formal.

• In English, never put a space before a colon, comma, exclamation point, full stop (period), question mark or semi-colon.

See also: Capitalisation.

Are Oxford commas necessary? No… and yes.

The Oxford comma, or serial comma, is used before a conjunction (such as “and”, “or”) in a list of three or more items. It is more commonly used in American English. OECD usage broadly aligns with British English usage; avoid using the Oxford comma unless necessary for clarity.

• Do not use a comma before the final item in a list.

  She had soup, bread and salad for lunch.

• Do put a comma before the final item in a list if its omission would cause confusion.

  They had soup, bread and cheese, and salad for lunch.

Ampersand

• Represented by “&”.

• The ampersand represents the word “and”.

• It is commonly used in company names and abbreviations as well as in informal writing.

Do

✔ Use the ampersand when part of an official name or title and when commonly used in an abbreviation (Johnson & Johnson, R&D).

Don’t

✘ Replace “and” with the ampersand in regular text or formal writing.

🙁 The report covers trends in health & education.

🙂 The report covers trends in health and education.

Apostrophe

• Represented by “’”.

• Apostrophes are used with “s” to indicate possession.

• In informal English, apostrophes can be used to indicate contraction.

Do

✔ Place an apostrophe followed by “s” to indicate possession for singular nouns, plural nouns that do not end in “s” and proper names (including those ending in “s”).

They considered the prime minister’s suggestion.

The children’s next school holiday is in April.

The airline lost Jane’s suitcase but not James’s suitcase.

✔ Place an apostrophe after the “s” for plural nouns that end in “s”.

The ministers’ decision was unanimous.

✔ Place the apostrophe after the last name or item in a series.

They met in Jean and Emilia’s office to review the report.

Don’t

✘ Use an apostrophe to contract words (“can’t” instead of “cannot”, “don’t” for “do not” or “they’re” for “they are”) except for informal text where character counts are limited, such as social media.

✘ Confuse “its” (a possessive pronoun) and “it’s” (a contraction of “it is”) or “your” (a possessive pronoun) and “you’re” (a contraction of “you are”).

✘ Use an apostrophe and “s” in decades or abbreviations.

🙁 The OECD and several other IO’s were founded in the 1960’s.

🙂 The OECD and several other IOs were founded in the 1960s.

Breaks and hard spaces

• Hard spaces between words ensure that words are not split during the document formatting stage.

Do

✔ Create hard spaces in Word^TM by holding Ctrl + Shift and pressing the space bar.

✔ Place a hard space (#) in the cases listed below.

Required use of hard spaces

 

Rule	Example
Between a person’s title and their name	Mr#Smith, Dr#Jones
Between a numeral and the unit or other word accompanying it	page#10, 37#firms, 19th#century
Within numerals made up of four or more digits	20#000#students
Between the day and month (but not month and year) in a date	15#January 2003
In country names	United#States
In currencies	EUR#50, USD#10#million
In units of measure (except °C and %)	580#kg, 215#cm, 42#hL
Other examples (depending on context, such as initials or abbreviations)	E.B.#White Smith,#J. (2025) French government e.g.#[text],#etc., et#al.

Colon

• Represented by “:”.

• Colons can be used to introduce information or clarification, or for emphasis.

• Use colons sparely: overuse reduces readability.

Do

✔ Use colons to lead into a list, explanation or elaboration or an indented quotation. In most such cases, the colon is preceded by an independent clause.

The OECD is located on two sites: one in Paris and one in Boulogne.

✔ Use colons to separate titles and subtitles.

Global Trends in Government Innovation 2024: Fostering Human-Centred Public Services

See also: Capitalisation; Lists.

Don’t

✘ Use more than one colon in a sentence.

✘ Put a space before a colon.

✘ Capitalise the first word after a colon (except for titles).

Comma

• Represented by “,”.

• A comma indicates a brief pause in a sentence. It may also be used to set off specific clauses, phrases or appositives as well as to separate items in a list.

Do

✔ Use commas to separate items in a list.

The Secretary-General visited Japan, Australia and New Zealand.

✔ Use a comma to set off a relative clause or other element that is not part of the main sentence.

Mr Smith, the committee chair, recommended a fully independent enquiry.

✔ Use a comma before conjunction introducing an independent clause.

It is one thing to know a gene’s chemical structure, but quite another to understand its actual function.

✔ Place a comma between adjectives if each modifies the noun alone and if you could insert the word “and” instead of the comma.

The board of directors called for swift, extensive changes.

Don’t

✘ Use commas:

• after “i.e.” or “e.g.”

• before parentheses

• before or after en‑dashes

• before “and” or “or” at the end of a sequence of items, unless one of the items includes another “and” or “or”.

Ellipses

• Represented by three dots “…”.

• In formal writing, an ellipsis (plural: ellipses) are used to show that text has been omitted or left unsaid.

• When placed in the middle of a sentence, an ellipsis suggests that something has been taken out; when placed at the end of the sentence, an ellipsis suggests there is more that could be said.

See also: Quotations.

Do

✔ Use to indicate material omitted from a quote, with a hard space placed before and after the ellipses (#...#).

This includes broader sectoral policies to induce emissions reductions by all actors along the supply chain … as well as policies that induce lifestyle or consumption changes in end users.

✔ Place brackets around the ellipsis when a full line or paragraph has been omitted, with a hard space placed before and after (#[...]#).

Governments are using open data initiatives, which foster transparency, accountability and citizen engagement, to improve public services. […] Open data allows for a collaborative approach to problem-solving.

Don’t

✘ Break an idea across section headings with ellipses; this is confusing for readers.

✘ Use an ellipsis to indicate a pause or to replace “etc.” or “and so on”.

✘ Put parentheses “( )” around an ellipsis.

✘ Put spaces between the dots in an ellipsis.

En-dash

• Represented by “–”.

• En‑dashes are used to set off information or add a phrase or clause to the sentence.

• En‑dashes can be confused with em-dashes and hyphens. See the table “Distinguishing between hyphens and dashes”.

Do

✔ Use en‑dashes in pairs to set off information that is not part of the main sentence, but which you wish to highlight or stress.

✔ Use a space before and after each en-dash.

The conference – for which more than 1 000 participants had registered – lasted three days.

✔ Use one en‑dash to add a phrase explaining or elaborating on what has gone before.

The meeting was running late – their discussion had been absorbing.

Don’t

✘ Use dashes – of any kind – in titles.

✘ Combine dashes with other punctuation; an interjected phrase that starts with a dash must end with one.

🙁 In a rush – it was late, he dashed out the door.

🙂 In a rush – it was late – he dashed out the door.

✘ Use em-dashes (—).

Distinguishing between hyphens and dashes

 

Type	Symbol	How to insert	Keystroke
Hyphen	-	Key on English keyboard: To the right of zero (0)	x2D + ALT x
En-dash	–	Windows shortcut: Crtl + minus sign	2013 + ALT x
Em-dash	—	Do not use in OECD work	Do not use in OECD work

Exclamation mark

• Represented by “!”.

• Exclamation marks are not used in formal writing. They may be used very sparingly in informal writing.

Forward slash

• They are used to indicate time periods and in expressing ratios and measurements.

• They are also used in internet addresses.

See also: Hyphenation; Time periods.

Do

✔ Use for a period overlapping two calendar years.

The accounts covered 2017/18.

✔ Use in ratios.

Price/earnings, reserves/production, risk/reward, USD 100/t, CO₂/km².

Don’t

✘ Use a slash mark (/) to replace “or”.

🙁 To go through customs you may present your ID card/passport/both.

🙂 To go through customs you may present your ID card, passport or both.

✘ Use “and/or” when “or” is sufficient.

✘ Use a slash for a period of two or more full years; instead, use a hyphen.

🙁 2017/19

🙂 2017‑2019 (but 2017/19 is correct to indicate a period that overlaps two years but is less than two full years).

✘ Use a slash to link terms that are usually linked by a hyphen.

🙁 A Paris/New York flight

🙂 A Paris-New York flight

✘ Replace “per”, “a” or “an” with a slash with units of measure.

🙁 100 kilometres/hour or 100 km/h

🙂 100 kilometres per hour.

Full stop (period)

• Represented by “.”.

• The full stop, or period, indicates the end of a sentence or statement.

Do

✔ Use a full stop to complete a sentence and follow it by a space.

✔ Place a full stop at end of all paragraphs.

✔ Put the full stop inside quotation marks when it ends the quotation as well as the sentence in which it appears. Place the full stop outside quotation marks where the quotation itself does not end with a full stop.

The chairperson said, “This meeting is concluded.”

The report often referred to “ups and downs”.

✔ Place a full stop after abbreviations such “etc.” and where generally customary (“i.e.” or “e.g.”).

✔ Include full stops when needed to avoid confusion.

No, they do not live at No. 20, their house is at No. 25.

See also: Breaks and hard spaces.

Don’t

✘ Use a full stop after headings, titles, or bulleted items unless they form a complete sentence.

✘ Use a full stop if an abbreviation consists of the first and last letters of a word: Mr, Ms, Ltd, Dr.

See also: Abbreviations, acronyms and signs.

Lists

• Lists can be useful to highlight important points or enumerate items.

• Bulleted lists are set off from the text, with a bullet point for each item.

• Numbered lists are run into the text and can use Arabic numbers (1, 2, 3), Roman numerals (i, ii, iii) or lowercase letters (a, b, c) as long as the choice is applied consistently.

• See table “Types of lists”.

Do

✔ Use lists sparingly, to avoid interrupting the flow of your text.

✔ Apply the same grammatical structure to each item in the list.

✔ For lists with complete sentences, use a capital letter to start the first word, and a full stop.

✔ For lists with incomplete sentences, use a lowercase letter to start the first word and no punctuation.

✔ Use bullet points, numbers (Arabic numbers or Roman numerals) or lowercase letters in roman type, to mark the items in the list.

Types of lists

 

Type	Example
Bulleted list with complete sentences	To avoid delays with your publication: Consult COM Support if you have questions. Submit your Kappa form six weeks in advance. Keep the publications team in COM appraised of any unexpected changes or delays. Send the complete manuscript to TRA as early as possible.
Numbered list with complete sentences (shown here with Arabic numerals; the same list style applies for Roman numerals)	PISA results show that: 1. Girls perform better in reading. 2. Boys perform better in mathematics. 3. Girls and boys perform better in reading when they read for pleasure in their free time.
All lists with incomplete sentences	The following components are essential to your publication: Title page Copyright page Foreword Executive summary
Run-in list in a paragraph	PISA results show that: girls perform better in reading; boys perform better in mathematics; and girls and boys perform better in reading when they read for pleasure in their free time.

Parentheses

• Represented by “( )”.

• Parentheses set off material that is not a part of the main sentence, such as an explanation. They are also used for in-text citation of a source.

Do

✔ Use sparingly to avoid jarring the reader; often commas can replace parentheses.

🙁 Mr Blair (the Prime Minister of the United Kingdom) addressed the United Nations.

🙂 Mr Blair, the Prime Minister of the United Kingdom, addressed the United Nations.

✔ Put the full stop before the closing parentheses mark if the phrase in parentheses is a complete sentence.

(The OECD Council met last week.)

✔ Put the full stop after the closing parentheses mark if the phrase in parentheses is not a complete sentence.

The committee met to discuss several topics (the latest report, new data and a project proposal).

Question mark

• Represented by “?”.

• Question marks are used to indicate direct questions.

See also: Quotations.

Do

✔ Use to mark direct questions, replacing the full stop.

✔ Use a capital letter to start the first word after the question mark.

Did the reporter read the policy paper? Apparently not.

Don’t

✘ Use a question mark for indirect questions.

🙁 The reporter was asked whether she had read the report?

🙂 The reporter was asked whether she had read the report.

Quotation marks

• Quotation marks come in pairs: one mark to open the quote and another to close it.

• Single quotation marks are indicated with (‘ ’), while double quotation marks are indicated with (“ ”). Each are used in different ways.

• Quotation marks enclose direct speech, quotations, titles or terms.

See also: Full stop (period); Quotations.

Do

✔ Use double quotation marks for direct speech, short quotations, titles or terms.

“The report discusses financial markets in Central and Eastern Europe.”

✔ Use single quotation marks for quotes within quotes

“The report discusses ‘grey markets’ in Central and Eastern Europe.”

✔ Place punctuation after the quotation mark when the quoted material does not end a sentence.

The report discusses “grey markets”, which are of particular concern in emerging economies.

✔ Place punctuation within the quotation mark if the quoted material ends with a full stop.

The report concluded that “continued growth is uncertain. The outlook remains cloudy.”

✔ Put punctuation after the close quotation mark if the quoted material itself does not end with a full stop and ends the sentence.

The speaker asserted that monetary policy must remain “vigilant”.

Don’t

✘ Use any quotation marks to set off quotations longer than five lines.

✘ Use single quotation marks for stand-alone terms.

🙁 This report refers to all ‘participants’ as defined below.

🙂 This report refers to all “participants” as defined below.

Semi-colon

• Represented by “;”.

• Semi-colons connect clauses that could stand alone as separate sentences, but which are linked for emphasis or because they are related.

• Semi-colons also clarify complex lists.

See also: Colon; Lists.

Do

✔ Use semi-colons to join related clauses.

✔ Separate items in complex lists that contain commas.

The committee reviewed the report; approval was unanimously given.

They visited Paris, France; Rome, Italy; and Athens, Greece.

Don’t

✘ Use semi-colons in simple lists.

🙁 They invested in Apple; IBM; Dell; and Microsoft.

🙂 They invested in Apple, IBM, Dell and Microsoft.

✘ Use semi-colons and colons interchangeably.

🙁 The team has one goal; success.

🙂 The team has one goal: success.

Square brackets

• Represented by “[ ]”.

• The note symbol is placed within square brackets and in subscript (OCDE, 2025_[1]).

See also: Quotations.

Do

✔ Use square brackets within other forms of punctuation, usually parentheses, to provide additional information or explanation.

(We also administered the Beck Depression Inventory [BDI; Beck, Steer, & Garbin, 1988], but those results are not reported here.)

✔ Use within direct quotes to note information not in the original.

The chair said, “At this point [2022], the outlook is still unclear.”

Key differences between English and French

 

English	French
Punctuation and hard spaces
Spaces are not placed between the last word and before punctuation, only after it. Source: OECD (2024), OECD Economic Outlook, Volume 2024 Issue 2, OECD Publishing, Paris, https://doi.org/10.1787/d8814e8b-en.	A space is placed after the last word and before a colon, semi-colon, exclamation point and question mark; spaces are placed before and after quotation marks. Source : OCDE (2024), Perspectives économiques de l'OCDE, Volume 2024 Numéro 2, Éditions OCDE, Paris, https://doi.org/10.1787/0481cf21-fr.
Quotation marks
Spaces are only placed before the opening mark and after the closing mark (if it is not followed by other punctuation).	Spaces are placed before and after quotation marks.
Double quotation marks (“ ”) are used for quotations and single (‘ ’) quotation marks are used for quotes within quotations.	French quotation marks (« ») are used for quotations and English double quotation marks (“ ”) are used for quotes within quotes.
Punctuation appears inside quotation marks if it concludes the phrase or sentence. “Taxes play a vital role in limiting the social and economic costs of smoking,” OECD Secretary-General Mathias Cormann said.	Punctuation appears outside quotation marks regardless of whether it concludes the phrase or sentence. « La fiscalité contribue de manière déterminante à limiter les coûts sociaux et économiques de la consommation de tabac », a déclaré le Secrétaire général de l’OCDE, Mathias Cormann.