diff --git a/spec/Markdown.md b/spec/Markdown.md
index 53cea6c..e73ee27 100644
--- a/spec/Markdown.md
+++ b/spec/Markdown.md
@@ -86,8 +86,7 @@ Todo: Links do not yet support a title attribute.
 
 ### Emphasis
 
-Wrapping asterisks *(\*)* indicate emphasis. Like Github-flavored
-Markdown, Spec Markdown does not treat underscore *(_)* as emphasis.
+Wrapping asterisks *(\*)* or underscores _(\_)_ indicate emphasis. 
 
 ```
 Example of **bold** and *italic* and ***bold italic***.
@@ -97,6 +96,14 @@ Produces the following:
 
 Example of **bold** and *italic* and ***bold italic***.
 
+```
+Example of **bold** and _italic_ and **_bold italic_**.
+```
+
+Produces the following:
+
+Example of **bold** and _italic_ and **_bold italic_**.
+
 
 
 ### Inline Code
diff --git a/spec/Spec Additions.md b/spec/Spec Additions.md
index 43f1b63..934bb55 100644
--- a/spec/Spec Additions.md	
+++ b/spec/Spec Additions.md	
@@ -24,15 +24,15 @@ referencing specific parts of your document easy. Try it here!
 
 ## Title and Introduction
 
-A Spec Markdown document should start with one Setext style header which will be
-used as the title of the document. Any content before the first atx (`#`) style
-header will become the introduction to the document.
+A Spec Markdown document should start with one bolded atx style header
+(`# **Title**`) which will be used as the title of the document. Any content
+before the next atx (`#`) style header will become the introduction to the
+document.
 
 A Spec Markdown document starts in this form:
 
 ```
-Spec Markdown
--------------
+# **Spec Markdown**
 
 Introductory paragraph.
 
diff --git a/src/grammar.pegjs b/src/grammar.pegjs
index 092362f..35e6117 100644
--- a/src/grammar.pegjs
+++ b/src/grammar.pegjs
@@ -12,6 +12,10 @@
     return list;
   }
 
+  function markdownUnescape(text) {
+    return text.replace(/\\([$_*])/g, '$1');
+  }
+
   var htmlBlockName;
 
   var BLOCK_TAGS_RX = /^(?:p|div|h[1-6]|blockquote|pre|table|dl|ol|ul|script|noscript|form|fieldset|iframe|math|ins|del)$/i;
@@ -27,16 +31,27 @@ document = title:title? contents:documentContent* EOF {
   };
 }
 
-title = BLOCK !'#' value:$NOT_NL+ NL ('---' '-'* / '===' '='*) &NL {
+oldTitle = BLOCK !'#' value:$NOT_NL+ NL ('---' '-'* / '===' '='*) &NL {
+  return {
+    type: 'DocumentTitle',
+    value: value
+  };
+}
+
+newTitle = BLOCK '# **' value:$([^*\r\n]+) '**' &NL {
   return {
     type: 'DocumentTitle',
     value: value
   };
 }
 
+title = newTitle / oldTitle
+
 SEC_CLOSE = _ '#'* &NL
 
-sectionTitle = $titleChar+
+sectionTitle = t:$titleChar+ {
+  return markdownUnescape(t);
+}
 titleChar = [^\n\r# ] / [# ] titleChar
 
 sectionID = start:$sectionIDStart rest:('.' $sectionIDPart)* '.' {
@@ -209,7 +224,7 @@ inlineEntity = inlineEdit / inlineCode / reference / bold / italic / link / imag
 content = inlineEntity / text
 
 textChar = escaped
-         / [^\n\r+\-{`*[!<]
+         / [^\n\r+\-{`*[!<_]
          / '++' !'}'
          / '+' !'+}'
          / '--' !'}'
@@ -221,7 +236,7 @@ textChar = escaped
 text = value:$textChar+ {
   return {
     type: 'Text',
-    value: value
+    value: markdownUnescape(value)
   };
 }
 
@@ -246,13 +261,22 @@ bold = '**' contents:(inlineCode / link / italic / text)+ '**' {
   };
 }
 
-italic = '*' contents:(inlineCode / link / text)+ '*' {
+asteriskItalic = '*' contents:(inlineCode / link / text)+ '*' {
   return {
     type: 'Italic',
     contents: contents
   };
 }
 
+underscoreItalic = '_' contents:(inlineCode / link / text)+ '_' {
+  return {
+    type: 'Italic',
+    contents: contents
+  };
+}
+
+italic = underscoreItalic / asteriskItalic
+
 inlineEdit = ins / del
 
 ins = '{++' contents:content* '++}' {
@@ -276,7 +300,7 @@ htmlTag = tag:$('<' '/'? [a-z]+ [^>]* '>') {
   };
 }
 
-reference = '{' !('++'/'--') _ ref:(call / value / token)? _ close:'}'? {
+reference = '{' !('++'/'--') __ ref:(call / value / token)? __ close:'}'? {
   if (ref === null || close === null) {
     error('Malformed {reference}.');
   }
@@ -344,7 +368,7 @@ linkTextChar = escaped
 linkText = value:$linkTextChar+ {
   return {
     type: 'Text',
-    value: value
+    value: markdownUnescape(value)
   };
 }
 
@@ -438,9 +462,16 @@ tableCellText = value:$tableCellTextChar+ {
 
 // Names
 
-localName = $([_a-z][_a-zA-Z0-9]*)
-globalName = $([A-Z][_a-zA-Z]*)
-paramName = $([_a-zA-Z][_a-zA-Z0-9]*)
+localName = text:$($('\\_' / [_a-z]) $('\\_' / [_a-zA-Z0-9])*) {
+  return markdownUnescape(text);
+}
+
+globalName = text:$([A-Z] $('\\_' / [_a-zA-Z])*) {
+  return markdownUnescape(text);
+}
+paramName = text:$($('\\_' / [_a-zA-Z]) $('\\_' / [_a-zA-Z0-9])*) {
+  return markdownUnescape(text);
+}
 
 
 // Algorithm
@@ -453,7 +484,7 @@ algorithm = BLOCK call:call _ ':' ':'? steps:list {
   };
 }
 
-call = name:(globalName / localName) '(' _ args:callArg* _ ')' {
+call = name:(globalName / localName) '(' __ args:callArg* __ ')' {
   return {
     type: 'Call',
     name: name,
@@ -461,7 +492,9 @@ call = name:(globalName / localName) '(' _ args:callArg* _ ')' {
   };
 }
 
-callArg = value:value [, ]* {
+callSep = __ ',' __ / __
+
+callArg = value:value callSep {
   return value;
 }
 
@@ -473,7 +506,7 @@ stringLiteral = '"' value:$([^"\n\r]/'\\"')* closer:'"'? {
   }
   return {
     type: 'StringLiteral',
-    value: '"' + value + '"'
+    value: '"' + markdownUnescape(value) + '"'
   };
 }
 
@@ -494,7 +527,7 @@ variable = name:localName {
 
 // Grammar productions
 
-semantic = BLOCK name:nonTerminal _ defType:(':::'/'::'/':') _ tokens:token+ steps:list {
+semantic = BLOCK name:nonTerminal _ defType:(':::'/'::'/':') _ tokens:tokenListMultiline steps:list {
   return {
     type: 'Semantic',
     name: name,
@@ -516,7 +549,7 @@ production = BLOCK token:nonTerminal _ defType:(':::'/'::'/':') _ rhs:production
   };
 }
 
-productionRHS = oneOfRHS / singleRHS / listRHS
+productionRHS = oneOfRHS / listRHS / singleRHS
 
 oneOfRHS = 'one of' rows:(_ NL? (_ token)+)+ {
   return {
@@ -529,7 +562,7 @@ oneOfRHS = 'one of' rows:(_ NL? (_ token)+)+ {
   };
 }
 
-singleRHS = condition:condition? _ tokens:token+ {
+singleRHS = condition:condition? _ tokens:tokenListMultiline {
   return {
     type: 'RHS',
     condition: condition,
@@ -545,7 +578,7 @@ indentedRHS = INDENT defs:(listItemRHS+)? DEDENT &{ return defs !== null; } {
   return defs;
 }
 
-listItemRHS = LINE listBullet _ condition:condition? _ tokens:token+ {
+listItemRHS = LINE listBullet _ condition:condition? _ tokens:tokenListMultiline {
   return {
     type: 'RHS',
     condition: condition,
@@ -561,13 +594,17 @@ condition = '[' condition:$('+' / '~' / 'if' (_ 'not')?) _ param:paramName ']' {
   };
 }
 
-token = token:unconstrainedToken quantifier:('+' / '?' / '*')? _ constraint:constraint? _ {
+constraintAfterGap = _ constraint:constraint {
+  return constraint;
+}
+
+token = token:unconstrainedToken quantifier:('+' / '?' / '*' / '\\*')? constraint:constraintAfterGap? {
   if (quantifier) {
     token = {
       type: 'Quantified',
       token: token,
-      isList: quantifier === '+' || quantifier === '*',
-      isOptional: quantifier === '?' || quantifier === '*'
+      isList: quantifier === '+' || quantifier === '*' || quantifier === '\\*',
+      isOptional: quantifier === '?' || quantifier === '*' || quantifier === '\\*'
     };
   }
   if (constraint) {
@@ -580,6 +617,22 @@ token = token:unconstrainedToken quantifier:('+' / '?' / '*')? _ constraint:cons
   return token;
 }
 
+tokenAfterSpace = _ token:token {
+  return token;
+}
+
+tokenAfterSpaceOrNewline = __ !listBullet token:token {
+  return token;
+}
+
+tokenListOneLine = head:token tail:tokenAfterSpace* {
+  return [head, ...tail];
+}
+
+tokenListMultiline = head:token tail:tokenAfterSpaceOrNewline* {
+  return [head, ...tail];
+}
+
 unconstrainedToken = prose / emptyToken / lookahead / nonTerminal / regexp / quotedTerminal / terminal
 
 prose = '"' text:$([^"\n\r]/'\\"')* closer:'"'? {
@@ -679,7 +732,7 @@ quotedTerminal = '`' value:$(([^`\n] / ('\\`'))+)? closer:'`' {
 terminal = value:$(([^ \n"/`] [^ \n"\`,\]\}]*)) {
   return {
     type: 'Terminal',
-    value: value
+    value: markdownUnescape(value)
   };
 }
 
@@ -711,6 +764,7 @@ DEDENT = &lineStart !{ indentStack.length === 0 } {
 NL = '\n' / '\r' / '\r\n'
 NOT_NL = [^\n\r]
 _ = ' '*
+__ = ' '* NL ' '* / ' '*
 EOF = NL* !.
 
 lineStart = NL+ / & { return offset() === 0 }
diff --git a/src/print.js b/src/print.js
index 60f809c..38caafd 100644
--- a/src/print.js
+++ b/src/print.js
@@ -42,6 +42,13 @@ function getPrismLanguage(lang) {
   if (!prism.languages[lang]) {
     loadAllLanguages();
   }
+  if (!prism.languages[lang] && lang.startsWith("raw")) {
+    // To prevent 'prettier' formatting code in your markdown, you may prefix
+    // the language with "raw" and we will still format it as you would expect
+    // in the output.
+    // e.g. ```graphql -> ```rawgraphql
+    return prism.languages[lang.substr(3)];
+  }
   return prism.languages[lang];
 }