diff --git a/.sasjslint b/.sasjslint
index e87f1cf..44e07e4 100644
--- a/.sasjslint
+++ b/.sasjslint
@@ -5,5 +5,6 @@
     "noSpacesInFileNames": true,
     "maxLineLength": 80,
     "lowerCaseFileNames": true,
-    "noTabIndentation": true
+    "noTabIndentation": true,
+    "indentationMultiple": 2
 }
\ No newline at end of file
diff --git a/src/Example File.sas b/src/Example File.sas
new file mode 100644
index 0000000..4056077
--- /dev/null
+++ b/src/Example File.sas	
@@ -0,0 +1,18 @@
+  
+  
+%macro mf_getuniquelibref(prefix=mclib,maxtries=1000);
+  %local x libref;
+  %let x={SAS002};
+   %do x=0 %to &maxtries;
+	%if %sysfunc(libref(&prefix&x)) ne 0 %then %do;
+  %let libref=&prefix&x;
+    %let rc=%sysfunc(libname(&libref,%sysfunc(pathname(work))));
+    %if &rc %then %put %sysfunc(sysmsg());
+    &prefix&x
+    %*put &sysmacroname: Libref &libref assigned as WORK and returned;
+    %return;
+  %end;
+  %end;
+  %put unable to find available libref in range &prefix.0-&maxtries;
+  %mend;
+
diff --git a/src/example file.sas b/src/example file.sas
deleted file mode 100644
index 3ff3243..0000000
--- a/src/example file.sas	
+++ /dev/null
@@ -1,17 +0,0 @@
-  
-  
- %macro mf_getuniquelibref(prefix=mclib,maxtries=1000);
-   %local x libref;
-   %let x={SAS002};
-   %do x=0 %to &maxtries;
-   %if %sysfunc(libref(&prefix&x)) ne 0 %then %do;
-     %let libref=&prefix&x;
-     %let rc=%sysfunc(libname(&libref,%sysfunc(pathname(work))));
-     %if &rc %then %put %sysfunc(sysmsg());
-     &prefix&x
-     %*put &sysmacroname: Libref &libref assigned as WORK and returned;
-     %return;
-   %end;
-   %end;
-   %put unable to find available libref in range &prefix.0-&maxtries;
- %mend;
\ No newline at end of file
diff --git a/src/example.ts b/src/example.ts
index dd25f2b..bae4de8 100644
--- a/src/example.ts
+++ b/src/example.ts
@@ -6,46 +6,45 @@ import path from 'path'
  */
 
 const text = `/**
-   @file
-   @brief Returns an unused libref
-   @details Use as follows:
+  @file
+  @brief Returns an unused libref
+  @details Use as follows:
   
-     libname mclib0 (work);
-     libname mclib1 (work);
-     libname mclib2 (work);
+    libname mclib0 (work);
+    libname mclib1 (work);
+    libname mclib2 (work);
   
-     %let libref=%mf_getuniquelibref({SAS001});
-     %put &=libref;
+    %let libref=%mf_getuniquelibref({SAS001});
+    %put &=libref;
   
-   which returns:
+  which returns:
   
  > mclib3
   
-   @param prefix= first part of libref.  Remember that librefs can only be 8 characters,
-     so a 7 letter prefix would mean that maxtries should be 10.
-   @param maxtries= the last part of the libref.  Provide an integer value.
+  @param prefix= first part of libref.  Remember that librefs can only be 8 characters,
+    so a 7 letter prefix would mean that maxtries should be 10.
+  @param maxtries= the last part of the libref.  Provide an integer value.
   
-   @version 9.2
-   @author Allan Bowe
+  @version 9.2
+  @author Allan Bowe
  **/
   
   
- %macro mf_getuniquelibref(prefix=mclib,maxtries=1000);
-	%local x libref;
-	%let x={SAS002};
+%macro mf_getuniquelibref(prefix=mclib,maxtries=1000);
+  %local x libref;
+  %let x={SAS002};
    %do x=0 %to &maxtries;
-   %if %sysfunc(libref(&prefix&x)) ne 0 %then %do;
-     %let libref=&prefix&x;
-     %let rc=%sysfunc(libname(&libref,%sysfunc(pathname(work))));
-     %if &rc %then %put %sysfunc(sysmsg());
-     &prefix&x
-     %*put &sysmacroname: Libref &libref assigned as WORK and returned;
-     %return;
-   %end;
-   %end;
-   %put unable to find available libref in range &prefix.0-&maxtries;
- %mend;
-
+	%if %sysfunc(libref(&prefix&x)) ne 0 %then %do;
+  %let libref=&prefix&x;
+    %let rc=%sysfunc(libname(&libref,%sysfunc(pathname(work))));
+    %if &rc %then %put %sysfunc(sysmsg());
+    &prefix&x
+    %*put &sysmacroname: Libref &libref assigned as WORK and returned;
+    %return;
+  %end;
+  %end;
+  %put unable to find available libref in range &prefix.0-&maxtries;
+  %mend;
 `
 
 lintText(text).then((diagnostics) => {
diff --git a/src/lint.spec.ts b/src/lint.spec.ts
index 9b6f5e2..d6d5e21 100644
--- a/src/lint.spec.ts
+++ b/src/lint.spec.ts
@@ -71,9 +71,9 @@ describe('lintText', () => {
 
 describe('lintFile', () => {
   it('should identify lint issues in a given file', async () => {
-    const results = await lintFile(path.join(__dirname, 'example file.sas'))
+    const results = await lintFile(path.join(__dirname, 'Example File.sas'))
 
-    expect(results.length).toEqual(5)
+    expect(results.length).toEqual(8)
     expect(results).toContainEqual({
       message: 'Line contains trailing spaces',
       lineNumber: 1,
@@ -95,6 +95,13 @@ describe('lintFile', () => {
       endColumnNumber: 1,
       severity: Severity.Warning
     })
+    expect(results).toContainEqual({
+      message: 'File name contains uppercase characters',
+      lineNumber: 1,
+      startColumnNumber: 1,
+      endColumnNumber: 1,
+      severity: Severity.Warning
+    })
     expect(results).toContainEqual({
       message: 'File missing Doxygen header',
       lineNumber: 1,
@@ -105,10 +112,24 @@ describe('lintFile', () => {
     expect(results).toContainEqual({
       message: 'Line contains encoded password',
       lineNumber: 5,
-      startColumnNumber: 11,
-      endColumnNumber: 19,
+      startColumnNumber: 10,
+      endColumnNumber: 18,
       severity: Severity.Error
     })
+    expect(results).toContainEqual({
+      message: 'Line is indented with a tab',
+      lineNumber: 7,
+      startColumnNumber: 1,
+      endColumnNumber: 1,
+      severity: Severity.Warning
+    })
+    expect(results).toContainEqual({
+      message: 'Line has incorrect indentation - 3 spaces',
+      lineNumber: 6,
+      startColumnNumber: 1,
+      endColumnNumber: 1,
+      severity: Severity.Warning
+    })
   })
 })
 
diff --git a/src/rules/indentationMultiple.spec.ts b/src/rules/indentationMultiple.spec.ts
new file mode 100644
index 0000000..830c055
--- /dev/null
+++ b/src/rules/indentationMultiple.spec.ts
@@ -0,0 +1,68 @@
+import { LintConfig, Severity } from '../types'
+import { indentationMultiple } from './indentationMultiple'
+
+describe('indentationMultiple', () => {
+  it('should return an empty array when the line is indented by two spaces', () => {
+    const line = "  %put 'hello';"
+    const config = new LintConfig({ indentationMultiple: 2 })
+    expect(indentationMultiple.test(line, 1, config)).toEqual([])
+  })
+
+  it('should return an empty array when the line is indented by a multiple of 2 spaces', () => {
+    const line = "      %put 'hello';"
+    const config = new LintConfig({ indentationMultiple: 2 })
+    expect(indentationMultiple.test(line, 1, config)).toEqual([])
+  })
+
+  it('should return an empty array when the line is not indented', () => {
+    const line = "%put 'hello';"
+    const config = new LintConfig({ indentationMultiple: 2 })
+    expect(indentationMultiple.test(line, 1, config)).toEqual([])
+  })
+
+  it('should return an array with a single diagnostic when the line is indented incorrectly', () => {
+    const line = "   %put 'hello';"
+    const config = new LintConfig({ indentationMultiple: 2 })
+    expect(indentationMultiple.test(line, 1, config)).toEqual([
+      {
+        message: `Line has incorrect indentation - 3 spaces`,
+        lineNumber: 1,
+        startColumnNumber: 1,
+        endColumnNumber: 1,
+        severity: Severity.Warning
+      }
+    ])
+  })
+
+  it('should return an array with a single diagnostic when the line is indented incorrectly', () => {
+    const line = "  %put 'hello';"
+    const config = new LintConfig({ indentationMultiple: 3 })
+    expect(indentationMultiple.test(line, 1, config)).toEqual([
+      {
+        message: `Line has incorrect indentation - 2 spaces`,
+        lineNumber: 1,
+        startColumnNumber: 1,
+        endColumnNumber: 1,
+        severity: Severity.Warning
+      }
+    ])
+  })
+
+  it('should fall back to a default of 2 spaces', () => {
+    const line = " %put 'hello';"
+    expect(indentationMultiple.test(line, 1)).toEqual([
+      {
+        message: `Line has incorrect indentation - 1 space`,
+        lineNumber: 1,
+        startColumnNumber: 1,
+        endColumnNumber: 1,
+        severity: Severity.Warning
+      }
+    ])
+  })
+
+  it('should return an empty array for lines within the default indentation', () => {
+    const line = "  %put 'hello';"
+    expect(indentationMultiple.test(line, 1)).toEqual([])
+  })
+})
diff --git a/src/rules/indentationMultiple.ts b/src/rules/indentationMultiple.ts
new file mode 100644
index 0000000..dee096d
--- /dev/null
+++ b/src/rules/indentationMultiple.ts
@@ -0,0 +1,37 @@
+import { LintConfig } from '../types'
+import { LineLintRule } from '../types/LintRule'
+import { LintRuleType } from '../types/LintRuleType'
+import { Severity } from '../types/Severity'
+
+const name = 'indentationMultiple'
+const description = 'Ensure indentation by a multiple of the configured number.'
+const message = 'Line has incorrect indentation'
+const test = (value: string, lineNumber: number, config?: LintConfig) => {
+  if (!value.startsWith(' ')) return []
+
+  const indentationMultiple = config?.indentationMultiple || 2
+  const numberOfSpaces = value.search(/\S|$/)
+  if (numberOfSpaces % indentationMultiple === 0) return []
+  return [
+    {
+      message: `${message} - ${numberOfSpaces} ${
+        numberOfSpaces === 1 ? 'space' : 'spaces'
+      }`,
+      lineNumber,
+      startColumnNumber: 1,
+      endColumnNumber: 1,
+      severity: Severity.Warning
+    }
+  ]
+}
+
+/**
+ * Lint rule that checks if a line is indented by a multiple of the configured indentation multiple.
+ */
+export const indentationMultiple: LineLintRule = {
+  type: LintRuleType.Line,
+  name,
+  description,
+  message,
+  test
+}
diff --git a/src/types/LintConfig.ts b/src/types/LintConfig.ts
index 91c0d08..f83de33 100644
--- a/src/types/LintConfig.ts
+++ b/src/types/LintConfig.ts
@@ -1,4 +1,5 @@
 import { hasDoxygenHeader } from '../rules/hasDoxygenHeader'
+import { indentationMultiple } from '../rules/indentationMultiple'
 import { lowerCaseFileNames } from '../rules/lowerCaseFileNames'
 import { maxLineLength } from '../rules/maxLineLength'
 import { noEncodedPasswords } from '../rules/noEncodedPasswords'
@@ -19,6 +20,7 @@ export class LintConfig {
   readonly fileLintRules: FileLintRule[] = []
   readonly pathLintRules: PathLintRule[] = []
   readonly maxLineLength = 80
+  readonly indentationMultiple = 2
 
   constructor(json?: any) {
     if (json?.noTrailingSpaces) {
@@ -38,6 +40,11 @@ export class LintConfig {
       this.lineLintRules.push(maxLineLength)
     }
 
+    if (json?.indentationMultiple) {
+      this.indentationMultiple = json.indentationMultiple
+      this.lineLintRules.push(indentationMultiple)
+    }
+
     if (json?.hasDoxygenHeader) {
       this.fileLintRules.push(hasDoxygenHeader)
     }
diff --git a/src/utils/getLintConfig.spec.ts b/src/utils/getLintConfig.spec.ts
index 8f9f64d..e7e4870 100644
--- a/src/utils/getLintConfig.spec.ts
+++ b/src/utils/getLintConfig.spec.ts
@@ -18,7 +18,7 @@ describe('getLintConfig', () => {
 
     expect(config).toBeInstanceOf(LintConfig)
     expect(config.fileLintRules.length).toEqual(1)
-    expect(config.lineLintRules.length).toEqual(4)
+    expect(config.lineLintRules.length).toEqual(5)
     expect(config.pathLintRules.length).toEqual(2)
   })
 })
diff --git a/src/utils/getLintConfig.ts b/src/utils/getLintConfig.ts
index be39867..c90b15d 100644
--- a/src/utils/getLintConfig.ts
+++ b/src/utils/getLintConfig.ts
@@ -13,7 +13,8 @@ export const DefaultLintConfiguration = {
   noSpacesInFileNames: true,
   lowerCaseFileNames: true,
   maxLineLength: 80,
-  noTabIndentation: true
+  noTabIndentation: true,
+  indentationMultiple: 2
 }
 
 /**