diff --git a/README.md b/README.md
index e48e402..0f1beb9 100644
--- a/README.md
+++ b/README.md
@@ -54,6 +54,9 @@ TidierStrings.jl currently supports:
 - `str_trim()`
 - `str_subset()`
 - `str_unique()`
+- `str_starts()`
+- `str_ends()`
+- `str_which()`
 - `word()`
 
 ## Examples
diff --git a/docs/src/index.md b/docs/src/index.md
index b4630ae..749dcad 100644
--- a/docs/src/index.md
+++ b/docs/src/index.md
@@ -25,4 +25,7 @@ This package includes:
 - `str_trim()`
 - `str_subset()`
 - `str_unique()`
+- `str_starts()`
+- `str_ends()`
+- `str_which()`
 - `word()`
diff --git a/src/TidierStrings.jl b/src/TidierStrings.jl
index 78cfc2a..9219f45 100644
--- a/src/TidierStrings.jl
+++ b/src/TidierStrings.jl
@@ -1,7 +1,7 @@
 module TidierStrings
 
 export str_detect, str_replace, str_replace_all, str_remove_all, str_remove, str_count, str_squish, str_equal, str_to_upper, str_to_lower, str_split, str_subset, 
-       str_to_title, str_to_sentence, str_dup, str_length, str_width, str_trim, str_unique, word
+       str_to_title, str_to_sentence, str_dup, str_length, str_width, str_trim, str_unique, word, str_starts, str_ends, str_which
 
 include("strings_docstrings.jl")
 
@@ -35,6 +35,55 @@ function str_detect(column, pattern::Union{String, Regex})
     end
 end
 
+"""
+$docstring_str_starts
+"""
+function str_starts(string::Vector{T}, pattern::Union{AbstractString,Regex}; negate::Bool=false)::Vector{Bool} where {T}
+    if pattern isa Regex
+        matches = [match(pattern, s) !== nothing for s in string]
+        return negate ? .!matches : matches
+    elseif pattern isa AbstractString
+        matches = [startswith(s, pattern) for s in string]
+        return negate ? .!matches : matches
+    else
+        error("Pattern must be either a Regex or an AbstractString.")
+    end
+end
+
+"""
+$docstring_str_ends
+"""
+function str_ends(string::Vector{T}, pattern::Union{AbstractString,Regex}; negate::Bool=false)::Vector{Bool} where {T}
+    if pattern isa Regex
+        matches = [match(pattern, s) !== nothing for s in string]
+        return negate ? .!matches : matches
+    elseif pattern isa AbstractString
+        matches = [endswith(s, pattern) for s in string]
+        return negate ? .!matches : matches
+    else
+        error("Pattern must be either a Regex or an AbstractString.")
+    end
+end
+
+"""
+$docstring_str_which
+"""
+function str_which(strings::Vector{T}, pattern::Union{AbstractString, Regex}; negate::Bool=false)::Vector{Int} where {T}
+    indices = Int[]
+    for (i, s) in enumerate(strings)
+        if pattern isa Regex && occursin(pattern, s)
+            push!(indices, i)
+        elseif pattern isa AbstractString && !ismissing(s) && occursin(pattern, s)
+            push!(indices, i)
+        end
+    end
+
+    if negate
+        return setdiff(1:length(strings), indices)
+    else
+        return indices
+    end
+end
 
 """
 $docstring_str_replace
diff --git a/src/strings_docstrings.jl b/src/strings_docstrings.jl
index d28797f..307ec8a 100644
--- a/src/strings_docstrings.jl
+++ b/src/strings_docstrings.jl
@@ -297,7 +297,8 @@ julia> str_to_sentence("hello world!")
 "Hello world!"
 
 julia> str_to_sentence("a sentence mUst starT With A capital letter.")
-"A sentence must start With a capital letter."
+"A sentence must start with a capital letter."
+```
 """
 
 const docstring_str_dup = 
@@ -317,6 +318,7 @@ Examples
 ```jldoctest
 julia> str_dup("hello", 3)
 "hellohellohello"
+```
 """
 
 const docstring_str_length = 
@@ -360,6 +362,7 @@ julia> str_width("hello world! 😊")
 
 julia> str_width("😊")
 2
+```
 """
 
 const docstring_str_trim = 
@@ -379,6 +382,7 @@ Examples
 ```jldoctest
 julia> str_trim("  hello world! 😊  ")
 "hello world! 😊"
+```
 """
 
 const docstring_str_unique =
@@ -402,6 +406,7 @@ julia> str_unique(["apple", "banana", "pear", "banana", "Apple"])
  "banana"
  "pear"
  "Apple"
+```
 """
 
 const docstring_word = 
@@ -422,20 +427,112 @@ The extracted word from the string.
 Examples
 ```jldoctest
 julia> word("Jane saw a cat", 1)
-1-element Vector{String}:
+1-element Vector{SubString{String}}:
  "Jane"
 
 julia> word("Jane saw a cat", 2)
-1-element Vector{String}:
+1-element Vector{SubString{String}}:
  "saw"
 
 julia> word("Jane saw a cat", -1)
-1-element Vector{String}:
+1-element Vector{SubString{String}}:
  "cat"
 
 julia> word("Jane saw a cat", 2, -1)
-3-element Vector{String}:
+3-element Vector{SubString{String}}:
  "saw"
  "a"
  "cat"
+```
+"""
+
+const docstring_str_starts =
+"""
+    str_starts(string::Vector{T}, pattern::Union{AbstractString, Regex}; negate::Bool=false)
+
+Check if a string starts with a certain pattern.
+
+Arguments
+- `string`: Input string.
+- `pattern`: The pattern to check for. Can be a string or a regular expression.
+- `negate`: Whether to negate the result. Default is `false`.
+
+Returns
+A vector of booleans indicating if the string starts with the pattern.
+
+Examples
+```jldoctest
+julia> str_starts(["apple", "banana", "pear", "pineapple"], r"^p")  # [false, false, true, true]
+4-element Vector{Bool}:
+ 0
+ 0
+ 1
+ 1
+julia> str_starts(["apple", "banana", "pear", "pineapple"], r"^p", negate=true)  # [true, true, false, false]
+4-element Vector{Bool}:
+ 1
+ 1
+ 0
+ 0
+```
+"""
+
+const docstring_str_ends =
+"""
+    str_ends(string::Vector{T}, pattern::Union{AbstractString, Regex}; negate::Bool=false)
+
+Check if a string ends with a certain pattern.
+
+Arguments
+- `string`: Input string.
+- `pattern`: The pattern to check for. Can be a string or a regular expression.
+- `negate`: Whether to negate the result. Default is `false`.
+
+Returns
+A vector of booleans indicating if the string ends with the pattern.
+
+Examples
+```jldoctest
+julia> str_ends(["apple", "banana", "pear", "pineapple"], r"e\$")  # [true, false, false, true]
+4-element Vector{Bool}:
+ 1
+ 0
+ 0
+ 1
+julia> str_ends(["apple", "banana", "pear", "pineapple"], r"e\$", negate=true)  # [false, true, true, false]
+4-element Vector{Bool}:
+ 0
+ 1
+ 1
+ 0
+```
+"""
+
+const docstring_str_which =
+"""
+    str_which(string::Vector{T}, pattern::Union{AbstractString, Regex}; negate::Bool=false)
+
+Returns the indices of strings where there's at least one match to the pattern.
+
+# Arguments
+- `string`: Input string.
+- `pattern`: The pattern to check for. Can be a string or a regular expression.
+- `negate`: Whether to negate the result. Default is `false`.
+
+# Returns
+An integer vector containing indices of matching strings.
+
+# Examples
+```jldoctest
+julia> str_which(["apple", "banana", "pear", "pineapple"], r"a")  # [1, 2, 3, 4]
+4-element Vector{Int64}:
+ 1
+ 2
+ 3
+ 4
+julia> str_which(["apple", "banana", "pear", "pineapple"], r"a", negate=true)  # []
+Int64[]
+julia> str_which(["apple", "banana", "pear", "pineapple"], "a", negate=true)  # []
+Int64[]
+```
 """
\ No newline at end of file