When retargeting previous actions or adding in-step logic within a survey, you'll use OR, AND and NOT logic to identify respondents who meet your desired criteria. 

OR logic

OR means respondents must meet at least one of the indicated criteria to qualify. 

Example: I want to target those who chose either Answer A or Answer C. 

Example: I want to target those who chose either Q1A2 or Q3A7. 

AND logic

AND means respondents must meet all of the indicated criteria to qualify. 

Example: I want to target those who chose both Answer A and Answer C.

Example: I want to target those who chose both Q1A2 and Q3A7.

NOT logic

NOT means respondents must not meet the criteria to qualify. 

Example: I want to target those who did NOT choose Answer B.

Example: I want to target those who did NOT choose Answer B or Answer C.*

Example: I want to target those who did NOT choose Q1A2 and Q3A7.* 

*When using NOT logic in conjunction with AND or OR logic, it reverses the functions of AND and OR. In other words, it causes AND to act as an OR operator, and OR to act as an AND operator. For example, imagine you want to exclude respondents who selected both "A" AND "B" (or the combination of A and B). While it’s intuitive to set your logic as NOT A AND NOT B, this will result in targeting respondents who selected either A or B. The correct way to target this group would be NOT A OR NOT B. 

Complex Logic

Retargeting logic can get complicated quickly when you’re working with multiple criteria. Often, it’s necessary to retarget multiple groups of multiple questions and responses to get to your desired audience. Think back to your days in algebra class, when you were working with brackets and parentheses in equations. This is similar. 

In the below example, imagine the targeting groups are the brackets, where one targeting group is shown in blue and the other targeting group is shown in green. Then, the questions and their response(s) are the parentheses within those brackets, where each is shown in purple. 

So how do we know when to separate questions into targeting groups? For each targeting group, you’re allowed to have exactly one logic operator to exist between the questions (each question is in purple parentheses). So there will be times when you’re targeting multiple questions and responses, and you can use a single targeting group, as long as the logic operators between them are consistent. It’s only when you need to mix logic operators that you may need to use multiple targeting groups. 

So in the above example, the reason we needed a second targeting group is because the green AND logic operator couldn’t be included in the same targeting group as the blue OR logic operators.